<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2022 Workiva-->
<!--r:b55d822a-88bf-4ec2-a70e-cd2a427fc307,g:7919d198-8cdb-4992-b067-0a73f637d995-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.wfscorp.com/role/ConsolidatedBalanceSheets" xlink:type="simple" xlink:href="int-20211231.xsd#ConsolidatedBalanceSheets"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/ConsolidatedBalanceSheets" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_d34f8266-f752-4588-ae2f-3b36d431b4c5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_d793422e-bc0d-422f-9c8a-b90a1b446399" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Liabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_d34f8266-f752-4588-ae2f-3b36d431b4c5" xlink:to="loc_us-gaap_Liabilities_d793422e-bc0d-422f-9c8a-b90a1b446399" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommitmentsAndContingencies_1b144a34-b278-4556-8c33-4a227e2cb773" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CommitmentsAndContingencies"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_d34f8266-f752-4588-ae2f-3b36d431b4c5" xlink:to="loc_us-gaap_CommitmentsAndContingencies_1b144a34-b278-4556-8c33-4a227e2cb773" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_380a3db0-9bb5-4397-9b7a-0dfa4f5a30a2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_d34f8266-f752-4588-ae2f-3b36d431b4c5" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_380a3db0-9bb5-4397-9b7a-0dfa4f5a30a2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_3f00de55-93b7-47d4-86d4-248894694dc0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetsCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_a54a2d3a-2d0a-4aa8-876b-4b7f4a21ada5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_3f00de55-93b7-47d4-86d4-248894694dc0" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_a54a2d3a-2d0a-4aa8-876b-4b7f4a21ada5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_7a600af9-e96c-4729-b0aa-06a0cc2697bf" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_3f00de55-93b7-47d4-86d4-248894694dc0" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_7a600af9-e96c-4729-b0aa-06a0cc2697bf" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InventoryNet_694f4b43-1e4a-49a0-8fb0-f42e7b19e9f9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InventoryNet"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_3f00de55-93b7-47d4-86d4-248894694dc0" xlink:to="loc_us-gaap_InventoryNet_694f4b43-1e4a-49a0-8fb0-f42e7b19e9f9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PrepaidExpenseCurrent_be3afc24-80ab-4b00-9961-d23ea0c8fa6c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PrepaidExpenseCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_3f00de55-93b7-47d4-86d4-248894694dc0" xlink:to="loc_us-gaap_PrepaidExpenseCurrent_be3afc24-80ab-4b00-9961-d23ea0c8fa6c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetsCurrent_38d4a040-7cbd-4b50-aa42-2f76c401aee2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeAssetsCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_3f00de55-93b7-47d4-86d4-248894694dc0" xlink:to="loc_us-gaap_DerivativeAssetsCurrent_38d4a040-7cbd-4b50-aa42-2f76c401aee2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsCurrent_af7c414d-3cee-417d-bf5a-d65449862400" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherAssetsCurrent"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_3f00de55-93b7-47d4-86d4-248894694dc0" xlink:to="loc_us-gaap_OtherAssetsCurrent_af7c414d-3cee-417d-bf5a-d65449862400" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_b91c1c6b-701c-4706-b533-dd1a0b8abbe8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_89a5dd97-b29d-496d-9ffa-3f96878ca05e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_b91c1c6b-701c-4706-b533-dd1a0b8abbe8" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_89a5dd97-b29d-496d-9ffa-3f96878ca05e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsPayableCurrent_16c92ba1-15b3-4fb8-96bc-2787e90a5a33" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccountsPayableCurrent"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_b91c1c6b-701c-4706-b533-dd1a0b8abbe8" xlink:to="loc_us-gaap_AccountsPayableCurrent_16c92ba1-15b3-4fb8-96bc-2787e90a5a33" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerRefundLiabilityCurrent_f4e80fb2-b51f-4730-8a46-75a462c0004b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ContractWithCustomerRefundLiabilityCurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_b91c1c6b-701c-4706-b533-dd1a0b8abbe8" xlink:to="loc_us-gaap_ContractWithCustomerRefundLiabilityCurrent_f4e80fb2-b51f-4730-8a46-75a462c0004b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_c386bc28-56de-4bbe-baa8-03e8abf7bb82" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_b91c1c6b-701c-4706-b533-dd1a0b8abbe8" xlink:to="loc_us-gaap_AccruedLiabilitiesCurrent_c386bc28-56de-4bbe-baa8-03e8abf7bb82" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilitiesCurrent_f87ae7e9-a6bf-4332-ab27-17365ba5ce1c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeLiabilitiesCurrent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_b91c1c6b-701c-4706-b533-dd1a0b8abbe8" xlink:to="loc_us-gaap_DerivativeLiabilitiesCurrent_f87ae7e9-a6bf-4332-ab27-17365ba5ce1c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_c8f4a9ba-2934-427d-a698-7990070e12ca" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Liabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesCurrent_fec9cb53-4c4a-4a3f-a924-c9a0288444da" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LiabilitiesCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_c8f4a9ba-2934-427d-a698-7990070e12ca" xlink:to="loc_us-gaap_LiabilitiesCurrent_fec9cb53-4c4a-4a3f-a924-c9a0288444da" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_5bd77061-26f6-44cf-a35b-178d8a123f3c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_c8f4a9ba-2934-427d-a698-7990070e12ca" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_5bd77061-26f6-44cf-a35b-178d8a123f3c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccruedIncomeTaxesNoncurrent_1f7749ec-ab55-4045-b64c-f8c3076f17d0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccruedIncomeTaxesNoncurrent"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_c8f4a9ba-2934-427d-a698-7990070e12ca" xlink:to="loc_us-gaap_AccruedIncomeTaxesNoncurrent_1f7749ec-ab55-4045-b64c-f8c3076f17d0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_02928d01-d476-4b81-87d1-58947d474d59" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_c8f4a9ba-2934-427d-a698-7990070e12ca" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_02928d01-d476-4b81-87d1-58947d474d59" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_d5e62ba2-8802-448e-8f13-7f959d0865fa" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Assets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsCurrent_889920cf-ae8d-4cc2-92ea-4577e1e870d6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d5e62ba2-8802-448e-8f13-7f959d0865fa" xlink:to="loc_us-gaap_AssetsCurrent_889920cf-ae8d-4cc2-92ea-4577e1e870d6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_09946476-fa54-436a-a2e7-999e811bd4b8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d5e62ba2-8802-448e-8f13-7f959d0865fa" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_09946476-fa54-436a-a2e7-999e811bd4b8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_57a9e69f-b949-41e7-8c75-c0c06ec44f6b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Goodwill"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d5e62ba2-8802-448e-8f13-7f959d0865fa" xlink:to="loc_us-gaap_Goodwill_57a9e69f-b949-41e7-8c75-c0c06ec44f6b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_IntangibleAssetsNetExcludingGoodwillAndOtherAssetsNoncurrent_192805af-ab0f-496c-b642-0231b7d64aa8" xlink:href="int-20211231.xsd#int_IntangibleAssetsNetExcludingGoodwillAndOtherAssetsNoncurrent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_d5e62ba2-8802-448e-8f13-7f959d0865fa" xlink:to="loc_int_IntangibleAssetsNetExcludingGoodwillAndOtherAssetsNoncurrent_192805af-ab0f-496c-b642-0231b7d64aa8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_2388d938-c7c9-4f3a-bca0-775fd1ec4b1f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquity"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockValue_4d80895c-6ade-4fee-b6d8-31264dc5d8d0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PreferredStockValue"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_2388d938-c7c9-4f3a-bca0-775fd1ec4b1f" xlink:to="loc_us-gaap_PreferredStockValue_4d80895c-6ade-4fee-b6d8-31264dc5d8d0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockValue_b9c57b13-704c-482d-8868-274896b4c617" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CommonStockValue"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_2388d938-c7c9-4f3a-bca0-775fd1ec4b1f" xlink:to="loc_us-gaap_CommonStockValue_b9c57b13-704c-482d-8868-274896b4c617" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalCommonStock_243f7a57-91a9-4852-a791-ed627740198b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AdditionalPaidInCapitalCommonStock"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_2388d938-c7c9-4f3a-bca0-775fd1ec4b1f" xlink:to="loc_us-gaap_AdditionalPaidInCapitalCommonStock_243f7a57-91a9-4852-a791-ed627740198b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_faec547d-826c-48c3-8fed-d87059176aa4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_2388d938-c7c9-4f3a-bca0-775fd1ec4b1f" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_faec547d-826c-48c3-8fed-d87059176aa4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_eba6d2bb-ae69-4b46-a9c1-65439907f2f8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_2388d938-c7c9-4f3a-bca0-775fd1ec4b1f" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_eba6d2bb-ae69-4b46-a9c1-65439907f2f8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_8a48f89a-69b3-4135-94bb-4d6242c83ef6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_014c5485-fc1b-4267-abfe-b75dc5a79248" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_StockholdersEquity"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_8a48f89a-69b3-4135-94bb-4d6242c83ef6" xlink:to="loc_us-gaap_StockholdersEquity_014c5485-fc1b-4267-abfe-b75dc5a79248" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterest_547a9b55-41e3-4a44-8b59-16a888822a49" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_MinorityInterest"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_8a48f89a-69b3-4135-94bb-4d6242c83ef6" xlink:to="loc_us-gaap_MinorityInterest_547a9b55-41e3-4a44-8b59-16a888822a49" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/ConsolidatedStatementsofIncomeandComprehensiveIncome" xlink:type="simple" xlink:href="int-20211231.xsd#ConsolidatedStatementsofIncomeandComprehensiveIncome"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/ConsolidatedStatementsofIncomeandComprehensiveIncome" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_66c393e6-b37c-403c-aeb1-2ebd84c9761e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GrossProfit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_f7b927a0-03de-445e-b2bd-d6760ce78f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Revenues"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_66c393e6-b37c-403c-aeb1-2ebd84c9761e" xlink:to="loc_us-gaap_Revenues_f7b927a0-03de-445e-b2bd-d6760ce78f7c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfRevenue_e548c72a-95e7-405c-92c8-b70aaf8b6dab" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CostOfRevenue"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_GrossProfit_66c393e6-b37c-403c-aeb1-2ebd84c9761e" xlink:to="loc_us-gaap_CostOfRevenue_e548c72a-95e7-405c-92c8-b70aaf8b6dab" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_78a1cd9b-73bf-4791-9bca-50b4cc44f71e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_90a3a627-a95d-48cf-b3f5-40408ffda003" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_78a1cd9b-73bf-4791-9bca-50b4cc44f71e" xlink:to="loc_us-gaap_ProfitLoss_90a3a627-a95d-48cf-b3f5-40408ffda003" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_9baf4798-4ba7-4474-bfe2-64756f2a9c06" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_78a1cd9b-73bf-4791-9bca-50b4cc44f71e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_9baf4798-4ba7-4474-bfe2-64756f2a9c06" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_0fecaee8-29d5-432a-b7cc-9ec1f99a48ac" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_65f196b0-fc10-4640-bc3a-3fac17eb649b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GrossProfit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_0fecaee8-29d5-432a-b7cc-9ec1f99a48ac" xlink:to="loc_us-gaap_GrossProfit_65f196b0-fc10-4640-bc3a-3fac17eb649b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_0a144e7b-1562-4d9d-a8ea-eb43e43a8f6a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingExpenses"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_0fecaee8-29d5-432a-b7cc-9ec1f99a48ac" xlink:to="loc_us-gaap_OperatingExpenses_0a144e7b-1562-4d9d-a8ea-eb43e43a8f6a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_687e8a84-341e-4974-9a83-a15eaf71c432" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_InterestIncomeExpenseAndOtherFinancialCostsNet_bed598e1-8e6f-497e-b44d-910fbdb29749" xlink:href="int-20211231.xsd#int_InterestIncomeExpenseAndOtherFinancialCostsNet"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NonoperatingIncomeExpense_687e8a84-341e-4974-9a83-a15eaf71c432" xlink:to="loc_int_InterestIncomeExpenseAndOtherFinancialCostsNet_bed598e1-8e6f-497e-b44d-910fbdb29749" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_9b02f80d-bce1-4c73-a809-b3b3480e9344" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NonoperatingIncomeExpense_687e8a84-341e-4974-9a83-a15eaf71c432" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_9b02f80d-bce1-4c73-a809-b3b3480e9344" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_22407836-224b-4c89-8ddf-223cc71933a9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_c2d42f91-5800-4a60-a753-ab41f9997bb5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_22407836-224b-4c89-8ddf-223cc71933a9" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_c2d42f91-5800-4a60-a753-ab41f9997bb5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_d00730d3-31a7-4542-935f-b2439bbb72df" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_22407836-224b-4c89-8ddf-223cc71933a9" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax_d00730d3-31a7-4542-935f-b2439bbb72df" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingExpenses_2fd2e0c7-991b-4f2d-8537-d08144292fe9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingExpenses"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCharges_8d474d2b-49e6-407c-80d4-33b122710880" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RestructuringCharges"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_2fd2e0c7-991b-4f2d-8537-d08144292fe9" xlink:to="loc_us-gaap_RestructuringCharges_8d474d2b-49e6-407c-80d4-33b122710880" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetImpairmentCharges_e185c823-d927-4c6b-acf8-e070a981a0b4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetImpairmentCharges"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_2fd2e0c7-991b-4f2d-8537-d08144292fe9" xlink:to="loc_us-gaap_AssetImpairmentCharges_e185c823-d927-4c6b-acf8-e070a981a0b4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_a1f84d75-9811-40b4-8262-7471a73632b6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_2fd2e0c7-991b-4f2d-8537-d08144292fe9" xlink:to="loc_us-gaap_GeneralAndAdministrativeExpense_a1f84d75-9811-40b4-8262-7471a73632b6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LaborAndRelatedExpense_22eff5cd-23fe-4c20-865b-81a8215c86d3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LaborAndRelatedExpense"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_2fd2e0c7-991b-4f2d-8537-d08144292fe9" xlink:to="loc_us-gaap_LaborAndRelatedExpense_22eff5cd-23fe-4c20-865b-81a8215c86d3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_25e40af1-f65e-4f4c-9711-f114b9e3889b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_896583c5-4633-4351-9fb7-798a8a624066" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_25e40af1-f65e-4f4c-9711-f114b9e3889b" xlink:to="loc_us-gaap_OperatingIncomeLoss_896583c5-4633-4351-9fb7-798a8a624066" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_976e0e6d-a996-4faf-9318-c12fe59a5167" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_25e40af1-f65e-4f4c-9711-f114b9e3889b" xlink:to="loc_us-gaap_NonoperatingIncomeExpense_976e0e6d-a996-4faf-9318-c12fe59a5167" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_8853030c-86b3-4c00-be45-024d170d7331" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetIncomeLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_9aa8131b-e73e-43ee-9888-267aa4f32040" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_8853030c-86b3-4c00-be45-024d170d7331" xlink:to="loc_us-gaap_ProfitLoss_9aa8131b-e73e-43ee-9888-267aa4f32040" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_a633db85-a771-40e5-84a1-7cdd56148c0a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_8853030c-86b3-4c00-be45-024d170d7331" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_a633db85-a771-40e5-84a1-7cdd56148c0a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_4417360c-e0d8-4a94-8a4e-a311c68d3931" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_4d47f328-f074-45bc-9266-c1a304ef6ecb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_4417360c-e0d8-4a94-8a4e-a311c68d3931" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_4d47f328-f074-45bc-9266-c1a304ef6ecb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_267b68c6-2f26-49da-a639-ad92e4e7dc52" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_4417360c-e0d8-4a94-8a4e-a311c68d3931" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_267b68c6-2f26-49da-a639-ad92e4e7dc52" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_12b29dbe-ab50-47ea-8aa5-277aa4752928" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProfitLoss"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_cdb25075-9b58-4587-8513-9a324d032694" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_12b29dbe-ab50-47ea-8aa5-277aa4752928" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_cdb25075-9b58-4587-8513-9a324d032694" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_33590ec0-5692-4fdd-bd24-d20c9fbceb2c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ProfitLoss_12b29dbe-ab50-47ea-8aa5-277aa4752928" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_33590ec0-5692-4fdd-bd24-d20c9fbceb2c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/ConsolidatedStatementsofCashFlows" xlink:type="simple" xlink:href="int-20211231.xsd#ConsolidatedStatementsofCashFlows"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/ConsolidatedStatementsofCashFlows" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2929b5f3-9084-433c-b1df-e8cc6119efbd" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_9b04b74c-0eb5-48ad-829e-4f26e458cf11" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProfitLoss"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2929b5f3-9084-433c-b1df-e8cc6119efbd" xlink:to="loc_us-gaap_ProfitLoss_9b04b74c-0eb5-48ad-829e-4f26e458cf11" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_ed4ca53f-cf37-4bff-bab0-006677e01ba4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_2929b5f3-9084-433c-b1df-e8cc6119efbd" xlink:to="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_ed4ca53f-cf37-4bff-bab0-006677e01ba4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8465c18b-a5cb-4440-b09e-058ba1552f0f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfDebt_7c2f8c46-6b70-4fe6-b944-6a5391117d2f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProceedsFromIssuanceOfDebt"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8465c18b-a5cb-4440-b09e-058ba1552f0f" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfDebt_7c2f8c46-6b70-4fe6-b944-6a5391117d2f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RepaymentsOfDebt_63508d56-7fe5-4352-aaf6-e8c370260a18" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RepaymentsOfDebt"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8465c18b-a5cb-4440-b09e-058ba1552f0f" xlink:to="loc_us-gaap_RepaymentsOfDebt_63508d56-7fe5-4352-aaf6-e8c370260a18" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsOfDividendsCommonStock_167a1d5a-a99d-46d7-9c6b-dc62094aa640" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsOfDividendsCommonStock"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8465c18b-a5cb-4440-b09e-058ba1552f0f" xlink:to="loc_us-gaap_PaymentsOfDividendsCommonStock_167a1d5a-a99d-46d7-9c6b-dc62094aa640" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_958280fc-2530-484b-96bb-b2d7dfd42bdc" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock"/>
    <link:calculationArc order="4" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8465c18b-a5cb-4440-b09e-058ba1552f0f" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_958280fc-2530-484b-96bb-b2d7dfd42bdc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_5da91190-4419-47ea-b7e5-004372bcfb89" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProceedsFromPaymentsForOtherFinancingActivities"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_8465c18b-a5cb-4440-b09e-058ba1552f0f" xlink:to="loc_us-gaap_ProceedsFromPaymentsForOtherFinancingActivities_5da91190-4419-47ea-b7e5-004372bcfb89" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_f84cb2ff-1857-48fb-afd7-130df47bc2b1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ad905deb-72a5-4848-9ed0-18c01f76321d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_f84cb2ff-1857-48fb-afd7-130df47bc2b1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ad905deb-72a5-4848-9ed0-18c01f76321d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_ec0bed65-5274-40d7-ab2a-c5dffc18b9d4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_f84cb2ff-1857-48fb-afd7-130df47bc2b1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_ec0bed65-5274-40d7-ab2a-c5dffc18b9d4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_4b7854b4-8b87-4eac-aa48-68b94f37726b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_f84cb2ff-1857-48fb-afd7-130df47bc2b1" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_4b7854b4-8b87-4eac-aa48-68b94f37726b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_c55b9137-221b-4c1b-bf10-37505f41433a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_f84cb2ff-1857-48fb-afd7-130df47bc2b1" xlink:to="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_c55b9137-221b-4c1b-bf10-37505f41433a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_60fb6a42-549f-4f57-ad69-642d6f313ad4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_e8aac223-b570-4b8f-a90a-2af40679fdb1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_60fb6a42-549f-4f57-ad69-642d6f313ad4" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_e8aac223-b570-4b8f-a90a-2af40679fdb1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_fad576ec-ae92-4e24-a634-105115573cbc" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_60fb6a42-549f-4f57-ad69-642d6f313ad4" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_fad576ec-ae92-4e24-a634-105115573cbc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_7d1e41cf-db9d-4a8b-854c-496e3ce8c6a8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsForProceedsFromOtherInvestingActivities"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_60fb6a42-549f-4f57-ad69-642d6f313ad4" xlink:to="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_7d1e41cf-db9d-4a8b-854c-496e3ce8c6a8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_5b6acae0-2021-46fc-abec-f5b73bd687bb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProceedsFromDivestitureOfBusinesses"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_60fb6a42-549f-4f57-ad69-642d6f313ad4" xlink:to="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_5b6acae0-2021-46fc-abec-f5b73bd687bb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_927bee45-afc8-4624-9714-4c77f3597d33" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_DepreciationAndAmortization_927bee45-afc8-4624-9714-4c77f3597d33" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_7da79439-481f-4331-baf0-3b175c07820d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ProvisionForDoubtfulAccounts"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_ProvisionForDoubtfulAccounts_7da79439-481f-4331-baf0-3b175c07820d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_ff08eab1-bae5-4f6e-b0e2-f1c2a81a4e7e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShareBasedCompensation"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_ShareBasedCompensation_ff08eab1-bae5-4f6e-b0e2-f1c2a81a4e7e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_DeferredIncomeTaxExpenseBenefitExcludingValuationAllowanceDeferredTaxAssetChangeInAmount_f297b1f4-7a6b-46fa-a83a-b017871c3cc5" xlink:href="int-20211231.xsd#int_DeferredIncomeTaxExpenseBenefitExcludingValuationAllowanceDeferredTaxAssetChangeInAmount"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_int_DeferredIncomeTaxExpenseBenefitExcludingValuationAllowanceDeferredTaxAssetChangeInAmount_f297b1f4-7a6b-46fa-a83a-b017871c3cc5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_RestructuringChargesWriteDownOfReceivables_eada6fdb-3b8d-48d0-a4b9-e4cba29d519f" xlink:href="int-20211231.xsd#int_RestructuringChargesWriteDownOfReceivables"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_int_RestructuringChargesWriteDownOfReceivables_eada6fdb-3b8d-48d0-a4b9-e4cba29d519f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossUnrealized_cf08a691-4562-4478-9cd0-d84c2cdd876a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ForeignCurrencyTransactionGainLossUnrealized"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossUnrealized_cf08a691-4562-4478-9cd0-d84c2cdd876a" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNoncashIncomeExpense_faa719b9-4bbf-4224-a45e-efb1a1baf032" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OtherNoncashIncomeExpense"/>
    <link:calculationArc order="7" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_OtherNoncashIncomeExpense_faa719b9-4bbf-4224-a45e-efb1a1baf032" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_1d76a08f-37d1-4687-97b0-a91df51665c2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <link:calculationArc order="8" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_1d76a08f-37d1-4687-97b0-a91df51665c2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_e10731bf-b4c3-4cef-a973-131eec91123d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <link:calculationArc order="9" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_e10731bf-b4c3-4cef-a973-131eec91123d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidExpense_82b0c3c9-c05d-4d0e-b89e-7638e0fea80e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidExpense"/>
    <link:calculationArc order="10" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidExpense_82b0c3c9-c05d-4d0e-b89e-7638e0fea80e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInDerivativeAssets_1cdecdd8-0afc-46bf-b866-2c6bfcbcdcb7" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInDerivativeAssets"/>
    <link:calculationArc order="11" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseInDerivativeAssets_1cdecdd8-0afc-46bf-b866-2c6bfcbcdcb7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherCurrentAssets_f64f7473-fadb-4aa4-8c00-06e2b7dca973" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInOtherCurrentAssets"/>
    <link:calculationArc order="12" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherCurrentAssets_f64f7473-fadb-4aa4-8c00-06e2b7dca973" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseCashCollateralFromCounterparties_38ad8c51-4646-440f-ad57-5cd6df847a03" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseCashCollateralFromCounterparties"/>
    <link:calculationArc order="13" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseCashCollateralFromCounterparties_38ad8c51-4646-440f-ad57-5cd6df847a03" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_11910349-b5bd-43f7-ae29-36cdd48e4cd0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentAssets"/>
    <link:calculationArc order="14" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherNoncurrentAssets_11910349-b5bd-43f7-ae29-36cdd48e4cd0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_d9a485f2-bed7-475c-bc05-74915def41b8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayable"/>
    <link:calculationArc order="15" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayable_d9a485f2-bed7-475c-bc05-74915def41b8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_IncreaseDecreaseInContractWithCustomerRefundLiability_f415d18f-5f79-4015-a556-d721ccdc6b2d" xlink:href="int-20211231.xsd#int_IncreaseDecreaseInContractWithCustomerRefundLiability"/>
    <link:calculationArc order="16" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_int_IncreaseDecreaseInContractWithCustomerRefundLiability_f415d18f-5f79-4015-a556-d721ccdc6b2d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_IncreaseDecreaseInAccruedExpensesAndOtherLiabilities_275e1881-a555-49e2-bed9-04a1aeab3975" xlink:href="int-20211231.xsd#int_IncreaseDecreaseInAccruedExpensesAndOtherLiabilities"/>
    <link:calculationArc order="17" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_int_IncreaseDecreaseInAccruedExpensesAndOtherLiabilities_275e1881-a555-49e2-bed9-04a1aeab3975" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_IncreaseDecreaseInIncomeTaxAndOtherLiabilitiesNoncurrent_c2adc75a-f553-493f-a8ef-0f5822667896" xlink:href="int-20211231.xsd#int_IncreaseDecreaseInIncomeTaxAndOtherLiabilitiesNoncurrent"/>
    <link:calculationArc order="18" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_int_IncreaseDecreaseInIncomeTaxAndOtherLiabilitiesNoncurrent_c2adc75a-f553-493f-a8ef-0f5822667896" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_47e4aa90-7503-4071-9362-23f22a53b55c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness"/>
    <link:calculationArc order="19" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivities_273f8176-2271-4eb4-9046-890ce4814452" xlink:to="loc_us-gaap_GainLossOnSaleOfBusiness_47e4aa90-7503-4071-9362-23f22a53b55c" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/AcquisitionsandDivestituresPurchasePriceAllocationDetails" xlink:type="simple" xlink:href="int-20211231.xsd#AcquisitionsandDivestituresPurchasePriceAllocationDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/AcquisitionsandDivestituresPurchasePriceAllocationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_69e03d17-0368-4ef3-b575-eae08801330b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_c4e5e4cc-0ce8-4c59-bf30-62674104b0f3" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationConsiderationTransferred1_69e03d17-0368-4ef3-b575-eae08801330b" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_c4e5e4cc-0ce8-4c59-bf30-62674104b0f3" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_d4c82175-9e66-4623-8770-6c50d8129801" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationConsiderationTransferred1_69e03d17-0368-4ef3-b575-eae08801330b" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferredLiabilitiesIncurred_d4c82175-9e66-4623-8770-6c50d8129801" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_c988657d-c30e-4c26-a0c4-0d64b5f690d4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_6b88459f-a0fc-4327-98b7-f41d90e337b9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_c988657d-c30e-4c26-a0c4-0d64b5f690d4" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable_6b88459f-a0fc-4327-98b7-f41d90e337b9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesOtherCurrentAndLongTermLiabilities_750668dc-7141-4651-ae7d-50690e6da880" xlink:href="int-20211231.xsd#int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesOtherCurrentAndLongTermLiabilities"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_c988657d-c30e-4c26-a0c4-0d64b5f690d4" xlink:to="loc_int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesOtherCurrentAndLongTermLiabilities_750668dc-7141-4651-ae7d-50690e6da880" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_475fdccc-9cbd-462e-938f-5372e6a874ac" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_c988657d-c30e-4c26-a0c4-0d64b5f690d4" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables_475fdccc-9cbd-462e-938f-5372e6a874ac" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsAndGoodwill_c1660b57-242f-48e2-8354-295727667a40" xlink:href="int-20211231.xsd#int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsAndGoodwill"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_c988657d-c30e-4c26-a0c4-0d64b5f690d4" xlink:to="loc_int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsAndGoodwill_c1660b57-242f-48e2-8354-295727667a40" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherCurrentAndLongTermAssets_9548f07e-f156-4a68-a509-b617e2afd2ae" xlink:href="int-20211231.xsd#int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherCurrentAndLongTermAssets"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_c988657d-c30e-4c26-a0c4-0d64b5f690d4" xlink:to="loc_int_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherCurrentAndLongTermAssets_9548f07e-f156-4a68-a509-b617e2afd2ae" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/PropertyandEquipmentDetails" xlink:type="simple" xlink:href="int-20211231.xsd#PropertyandEquipmentDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/PropertyandEquipmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_1b8df03b-b971-40da-aa68-42389588cd43" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_73451b7c-dff8-45d5-ab75-20172bc82eca" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_1b8df03b-b971-40da-aa68-42389588cd43" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetBeforeAccumulatedDepreciationAndAmortization_73451b7c-dff8-45d5-ab75-20172bc82eca" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_4015e077-5b3c-4301-9243-86e1f7d789ac" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization_1b8df03b-b971-40da-aa68-42389588cd43" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAccumulatedDepreciationAndAmortization_4015e077-5b3c-4301-9243-86e1f7d789ac" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedComputerSoftwareNet_841e04ff-ad8c-4a9e-8c76-8048d974eaec" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CapitalizedComputerSoftwareNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedComputerSoftwareAccumulatedAmortization_9a3f680f-a82d-47e6-90ec-08fafbe1431f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CapitalizedComputerSoftwareAccumulatedAmortization"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CapitalizedComputerSoftwareNet_841e04ff-ad8c-4a9e-8c76-8048d974eaec" xlink:to="loc_us-gaap_CapitalizedComputerSoftwareAccumulatedAmortization_9a3f680f-a82d-47e6-90ec-08fafbe1431f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedComputerSoftwareGross_55ad484f-454e-41d9-8980-cb5ca1318430" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CapitalizedComputerSoftwareGross"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CapitalizedComputerSoftwareNet_841e04ff-ad8c-4a9e-8c76-8048d974eaec" xlink:to="loc_us-gaap_CapitalizedComputerSoftwareGross_55ad484f-454e-41d9-8980-cb5ca1318430" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/GoodwillandIdentifiableIntangibleAssetsIdentifiableIntangibleAssetsDetails" xlink:type="simple" xlink:href="int-20211231.xsd#GoodwillandIdentifiableIntangibleAssetsIdentifiableIntangibleAssetsDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/GoodwillandIdentifiableIntangibleAssetsIdentifiableIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_63252f4c-6acf-4fc9-9ffb-66cb37049b8b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_c4d67ca1-604c-46d6-bacb-10236b88545b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_63252f4c-6acf-4fc9-9ffb-66cb37049b8b" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_c4d67ca1-604c-46d6-bacb-10236b88545b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_b0d01787-820c-45ba-93ca-a5b59d52f712" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_63252f4c-6acf-4fc9-9ffb-66cb37049b8b" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_b0d01787-820c-45ba-93ca-a5b59d52f712" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_c579d4a4-ac63-4b53-81c7-32d4bf0f76cf" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_16bb0396-bc4f-45f8-ae2d-b03461d51e11" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_c579d4a4-ac63-4b53-81c7-32d4bf0f76cf" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_16bb0396-bc4f-45f8-ae2d-b03461d51e11" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_8464eb9e-4305-47ca-a082-0ed7bfb22fd1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_c579d4a4-ac63-4b53-81c7-32d4bf0f76cf" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_8464eb9e-4305-47ca-a082-0ed7bfb22fd1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_78d45840-ad36-40e0-8a3c-98c66011a502" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_566d4e30-4da8-43d5-a729-b18f7ed4f137" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_78d45840-ad36-40e0-8a3c-98c66011a502" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_566d4e30-4da8-43d5-a729-b18f7ed4f137" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_6f4d1f86-f759-4e8f-b3d6-7d70ac553d0d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_78d45840-ad36-40e0-8a3c-98c66011a502" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_6f4d1f86-f759-4e8f-b3d6-7d70ac553d0d" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/GoodwillandIdentifiableIntangibleAssetsIdentifiableIntangibleAssetsDetails_1" xlink:type="simple" xlink:href="int-20211231.xsd#GoodwillandIdentifiableIntangibleAssetsIdentifiableIntangibleAssetsDetails_1"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/GoodwillandIdentifiableIntangibleAssetsIdentifiableIntangibleAssetsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_cd6520e5-8ec3-4132-bd50-1b806ae16f39" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_293aa34a-1c69-4455-baa8-f74cb541cde8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_cd6520e5-8ec3-4132-bd50-1b806ae16f39" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_293aa34a-1c69-4455-baa8-f74cb541cde8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_8f51725a-f4d0-453d-a243-13416f7c6672" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_cd6520e5-8ec3-4132-bd50-1b806ae16f39" xlink:to="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_8f51725a-f4d0-453d-a243-13416f7c6672" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/GoodwillandIdentifiableIntangibleAssetsFutureEstimatedAmortizationofIdentifiableIntangibleAssetsDetails" xlink:type="simple" xlink:href="int-20211231.xsd#GoodwillandIdentifiableIntangibleAssetsFutureEstimatedAmortizationofIdentifiableIntangibleAssetsDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/GoodwillandIdentifiableIntangibleAssetsFutureEstimatedAmortizationofIdentifiableIntangibleAssetsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_55e1b642-15f8-4308-8577-2aeb379e7966" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_aafd54d8-9c61-426e-aac5-2c2c9e40f7ec" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_55e1b642-15f8-4308-8577-2aeb379e7966" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_aafd54d8-9c61-426e-aac5-2c2c9e40f7ec" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_6eb22252-c9bd-44ca-9e1c-94c173aa80bd" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_55e1b642-15f8-4308-8577-2aeb379e7966" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_6eb22252-c9bd-44ca-9e1c-94c173aa80bd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_06149fe9-f6f6-4d60-be61-29cd1f7af8da" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_55e1b642-15f8-4308-8577-2aeb379e7966" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_06149fe9-f6f6-4d60-be61-29cd1f7af8da" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_bd57e8d3-1246-4913-941a-4fe0f73956c0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_55e1b642-15f8-4308-8577-2aeb379e7966" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_bd57e8d3-1246-4913-941a-4fe0f73956c0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_05d87c7e-0384-45fd-9254-89f98f620f7c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_55e1b642-15f8-4308-8577-2aeb379e7966" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_05d87c7e-0384-45fd-9254-89f98f620f7c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_a88ad015-7640-4a42-8b26-320063efde70" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_55e1b642-15f8-4308-8577-2aeb379e7966" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_a88ad015-7640-4a42-8b26-320063efde70" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsSummaryofDebtDetails" xlink:type="simple" xlink:href="int-20211231.xsd#DebtInterestIncomeExpenseandOtherFinanceCostsSummaryofDebtDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsSummaryofDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_846bdf22-4478-43c8-828e-1fbcbe17fcb8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_1528d0bc-861f-4fa2-9649-e404232153a8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_846bdf22-4478-43c8-828e-1fbcbe17fcb8" xlink:to="loc_us-gaap_FinanceLeaseLiability_1528d0bc-861f-4fa2-9649-e404232153a8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_6a4e28e0-012b-47ea-9909-c1c03cde2fd4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebt"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_846bdf22-4478-43c8-828e-1fbcbe17fcb8" xlink:to="loc_us-gaap_LongTermDebt_6a4e28e0-012b-47ea-9909-c1c03cde2fd4" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsSummaryofDebtDetails_1" xlink:type="simple" xlink:href="int-20211231.xsd#DebtInterestIncomeExpenseandOtherFinanceCostsSummaryofDebtDetails_1"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsSummaryofDebtDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_6a8b2305-0af1-465c-8c5e-55d73467184b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_84c0cd52-da99-41fe-a764-959f6c941003" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_6a8b2305-0af1-465c-8c5e-55d73467184b" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent_84c0cd52-da99-41fe-a764-959f6c941003" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_de9840d7-d429-44a4-be3f-f96532d87874" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LongTermDebtAndCapitalLeaseObligations"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebtAndCapitalLeaseObligationsIncludingCurrentMaturities_6a8b2305-0af1-465c-8c5e-55d73467184b" xlink:to="loc_us-gaap_LongTermDebtAndCapitalLeaseObligations_de9840d7-d429-44a4-be3f-f96532d87874" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsAggregateAnnualMaturitiesDetails" xlink:type="simple" xlink:href="int-20211231.xsd#DebtInterestIncomeExpenseandOtherFinanceCostsAggregateAnnualMaturitiesDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsAggregateAnnualMaturitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtAndCapitalLeaseObligations_c0ea6086-0cc0-4848-bc75-fabcf94dbcc0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DebtAndCapitalLeaseObligations"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInNextTwelveMonths_670b8288-6e37-4570-8524-3c8dee30b9fc" xlink:href="int-20211231.xsd#int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInNextTwelveMonths"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtAndCapitalLeaseObligations_c0ea6086-0cc0-4848-bc75-fabcf94dbcc0" xlink:to="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInNextTwelveMonths_670b8288-6e37-4570-8524-3c8dee30b9fc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearTwo_f97534dd-0c04-48c0-8454-c2eebb68db2b" xlink:href="int-20211231.xsd#int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearTwo"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtAndCapitalLeaseObligations_c0ea6086-0cc0-4848-bc75-fabcf94dbcc0" xlink:to="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearTwo_f97534dd-0c04-48c0-8454-c2eebb68db2b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearThree_bfcb9158-7811-4324-8e69-c7d59a4006d0" xlink:href="int-20211231.xsd#int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearThree"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtAndCapitalLeaseObligations_c0ea6086-0cc0-4848-bc75-fabcf94dbcc0" xlink:to="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearThree_bfcb9158-7811-4324-8e69-c7d59a4006d0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearFour_060ebcfb-9754-4df1-b291-e3e176e17368" xlink:href="int-20211231.xsd#int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearFour"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtAndCapitalLeaseObligations_c0ea6086-0cc0-4848-bc75-fabcf94dbcc0" xlink:to="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearFour_060ebcfb-9754-4df1-b291-e3e176e17368" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearFive_cd3c46ea-bbe2-4afc-b136-7bc36083e53f" xlink:href="int-20211231.xsd#int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearFive"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtAndCapitalLeaseObligations_c0ea6086-0cc0-4848-bc75-fabcf94dbcc0" xlink:to="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalInYearFive_cd3c46ea-bbe2-4afc-b136-7bc36083e53f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalAfterYearFive_bf554877-bb48-457d-9d79-b1a1f726b157" xlink:href="int-20211231.xsd#int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalAfterYearFive"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtAndCapitalLeaseObligations_c0ea6086-0cc0-4848-bc75-fabcf94dbcc0" xlink:to="loc_int_LongTermDebtAndFinanceLeaseLiabilityRepaymentsOfPrincipalAfterYearFive_bf554877-bb48-457d-9d79-b1a1f726b157" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsInterestIncomeExpenseandOtherFinancingCostsDetails" xlink:type="simple" xlink:href="int-20211231.xsd#DebtInterestIncomeExpenseandOtherFinanceCostsInterestIncomeExpenseandOtherFinancingCostsDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/DebtInterestIncomeExpenseandOtherFinanceCostsInterestIncomeExpenseandOtherFinancingCostsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_int_InterestIncomeExpenseAndOtherFinancialCostsNet_d614c89b-ab02-432f-a44c-c8ba1751e661" xlink:href="int-20211231.xsd#int_InterestIncomeExpenseAndOtherFinancialCostsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentIncomeInterest_7696ffa7-c5a1-43e3-ae21-e71e7b28e0ae" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InvestmentIncomeInterest"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_int_InterestIncomeExpenseAndOtherFinancialCostsNet_d614c89b-ab02-432f-a44c-c8ba1751e661" xlink:to="loc_us-gaap_InvestmentIncomeInterest_7696ffa7-c5a1-43e3-ae21-e71e7b28e0ae" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpense_8ecc869d-cbbb-4070-94cb-1f72a3a0fb8f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InterestExpense"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_int_InterestIncomeExpenseAndOtherFinancialCostsNet_d614c89b-ab02-432f-a44c-c8ba1751e661" xlink:to="loc_us-gaap_InterestExpense_8ecc869d-cbbb-4070-94cb-1f72a3a0fb8f" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/IncomeTaxesTaxProvisionBenefitReconciliationandTaxRatesDetails" xlink:type="simple" xlink:href="int-20211231.xsd#IncomeTaxesTaxProvisionBenefitReconciliationandTaxRatesDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/IncomeTaxesTaxProvisionBenefitReconciliationandTaxRatesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_4c209e7f-9d4c-4130-9366-1ed6484e493a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_101cc9f0-647a-4cc5-a243-5956510b6cf7" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_4c209e7f-9d4c-4130-9366-1ed6484e493a" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic_101cc9f0-647a-4cc5-a243-5956510b6cf7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_3d01c70d-215f-49b0-93ba-aa652bae75a5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_4c209e7f-9d4c-4130-9366-1ed6484e493a" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign_3d01c70d-215f-49b0-93ba-aa652bae75a5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_c6a6de22-2af2-4099-9509-41fc9e3b168a" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_dd53c9aa-1e54-4322-82e6-ca4031173281" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredFederalIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_c6a6de22-2af2-4099-9509-41fc9e3b168a" xlink:to="loc_us-gaap_DeferredFederalIncomeTaxExpenseBenefit_dd53c9aa-1e54-4322-82e6-ca4031173281" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_27cf5bda-d8eb-4bd1-8fb5-30ca8e49ded7" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_c6a6de22-2af2-4099-9509-41fc9e3b168a" xlink:to="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_27cf5bda-d8eb-4bd1-8fb5-30ca8e49ded7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_21984a90-6bd1-4b6e-a367-ba0b1462003b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredForeignIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_c6a6de22-2af2-4099-9509-41fc9e3b168a" xlink:to="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit_21984a90-6bd1-4b6e-a367-ba0b1462003b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_76a97f4e-dd42-46f7-ad7a-4f847f6c6556" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_c986064a-1368-4372-be02-32a843d60c89" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CurrentIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_76a97f4e-dd42-46f7-ad7a-4f847f6c6556" xlink:to="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_c986064a-1368-4372-be02-32a843d60c89" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_d8aa0a15-d25c-4ea4-8744-708115ef3eb5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_76a97f4e-dd42-46f7-ad7a-4f847f6c6556" xlink:to="loc_us-gaap_DeferredIncomeTaxExpenseBenefit_d8aa0a15-d25c-4ea4-8744-708115ef3eb5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_NoncurrentIncomeTaxExpenseBenefit_156d7cc2-5c2b-490d-ad73-12b306ef087f" xlink:href="int-20211231.xsd#int_NoncurrentIncomeTaxExpenseBenefit"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_76a97f4e-dd42-46f7-ad7a-4f847f6c6556" xlink:to="loc_int_NoncurrentIncomeTaxExpenseBenefit_156d7cc2-5c2b-490d-ad73-12b306ef087f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_c94efa4a-3641-4a84-bb6f-a190f198dc8d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_c94efa4a-3641-4a84-bb6f-a190f198dc8d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_cd25e1bc-69b9-4115-9cd8-532dfb4d8852" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxRateDifferential_cd25e1bc-69b9-4115-9cd8-532dfb4d8852" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_17dc98f8-ad2c-4fb0-813e-ddae64ee8591" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes_17dc98f8-ad2c-4fb0-813e-ddae64ee8591" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomePercent_9fabf66d-2715-4a36-94c7-e2877889a7c2" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomePercent"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationGlobalIntangibleLowTaxedIncomePercent_9fabf66d-2715-4a36-94c7-e2877889a7c2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationBaseErosionAndAntiAbuseTaxPercent_90d900f8-7c45-4827-9d8b-d5b21f523e6f" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationBaseErosionAndAntiAbuseTaxPercent"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationBaseErosionAndAntiAbuseTaxPercent_90d900f8-7c45-4827-9d8b-d5b21f523e6f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_37262699-1412-4450-a3cc-5d966c470572" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTaxContingencies_37262699-1412-4450-a3cc-5d966c470572" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationForeignCurrencyAdjustmentsPercent_b09d9dc2-f0ab-4d58-af9d-5339a98366d5" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationForeignCurrencyAdjustmentsPercent"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationForeignCurrencyAdjustmentsPercent_b09d9dc2-f0ab-4d58-af9d-5339a98366d5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationIntercompanyPricingAdjustment_818ba9a3-8d5d-4167-825a-00ed8d3fd5e2" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationIntercompanyPricingAdjustment"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationIntercompanyPricingAdjustment_818ba9a3-8d5d-4167-825a-00ed8d3fd5e2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationDeductionInterestIncomePercent_2fb3e7f4-dc3d-4092-97b6-a71174ef9cc6" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationDeductionInterestIncomePercent"/>
    <link:calculationArc order="9" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationDeductionInterestIncomePercent_2fb3e7f4-dc3d-4092-97b6-a71174ef9cc6" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestExpensePercent_3b61478f-5643-466c-adc0-8cd52dd8b06e" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestExpensePercent"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseInterestExpensePercent_3b61478f-5643-466c-adc0-8cd52dd8b06e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_f8d535fe-842f-4a33-8476-90acd56850f4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance"/>
    <link:calculationArc order="11" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance_f8d535fe-842f-4a33-8476-90acd56850f4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_006f011b-6cff-47ce-a550-1abca77db7d5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther"/>
    <link:calculationArc order="12" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther_006f011b-6cff-47ce-a550-1abca77db7d5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationSaleOfCompanyPercent_d77d3b26-6bab-461f-a5ea-efde5eaca7cd" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationSaleOfCompanyPercent"/>
    <link:calculationArc order="13" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationSaleOfCompanyPercent_d77d3b26-6bab-461f-a5ea-efde5eaca7cd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensationPercent_18f72904-effa-4fcd-af80-d5438edf26ad" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensationPercent"/>
    <link:calculationArc order="14" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOfficerCompensationPercent_18f72904-effa-4fcd-af80-d5438edf26ad" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationStatutoryAdjustments_b12172c8-1dc2-402d-b2a7-2d098f5c49f2" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationStatutoryAdjustments"/>
    <link:calculationArc order="15" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationStatutoryAdjustments_b12172c8-1dc2-402d-b2a7-2d098f5c49f2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_EffectiveIncomeTaxRateReconciliationUKTaxRateChange_efefdf34-dbe6-45de-8c5f-b912feb07feb" xlink:href="int-20211231.xsd#int_EffectiveIncomeTaxRateReconciliationUKTaxRateChange"/>
    <link:calculationArc order="16" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_fc82b2bc-8714-4999-b03f-f61ce769a740" xlink:to="loc_int_EffectiveIncomeTaxRateReconciliationUKTaxRateChange_efefdf34-dbe6-45de-8c5f-b912feb07feb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_4ee049df-0f9e-4b5e-9862-1a914b8ce87f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CurrentIncomeTaxExpenseBenefit"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentFederalTaxExpenseBenefit_6a8eb5a1-644e-4440-bf42-3166d0a8153e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CurrentFederalTaxExpenseBenefit"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_4ee049df-0f9e-4b5e-9862-1a914b8ce87f" xlink:to="loc_us-gaap_CurrentFederalTaxExpenseBenefit_6a8eb5a1-644e-4440-bf42-3166d0a8153e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_3dad0ee4-7003-47e2-a613-e590abb5e926" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CurrentStateAndLocalTaxExpenseBenefit"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_4ee049df-0f9e-4b5e-9862-1a914b8ce87f" xlink:to="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit_3dad0ee4-7003-47e2-a613-e590abb5e926" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CurrentForeignTaxExpenseBenefit_5aa6c966-0e3e-4931-8b6e-b37474e144a0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_CurrentForeignTaxExpenseBenefit"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefit_4ee049df-0f9e-4b5e-9862-1a914b8ce87f" xlink:to="loc_us-gaap_CurrentForeignTaxExpenseBenefit_5aa6c966-0e3e-4931-8b6e-b37474e144a0" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/IncomeTaxesTemporaryDifferencesDetails" xlink:type="simple" xlink:href="int-20211231.xsd#IncomeTaxesTemporaryDifferencesDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/IncomeTaxesTemporaryDifferencesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilities_e5d6dadf-5627-4aeb-8d26-d884dd3576ed" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredIncomeTaxLiabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_b2389e8b-c65e-4a57-9631-e7595fad3d33" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_e5d6dadf-5627-4aeb-8d26-d884dd3576ed" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesPropertyPlantAndEquipment_b2389e8b-c65e-4a57-9631-e7595fad3d33" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets_b4609962-ffbf-430c-ad4c-aaf0ead89622" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_e5d6dadf-5627-4aeb-8d26-d884dd3576ed" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssets_b4609962-ffbf-430c-ad4c-aaf0ead89622" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesPrepaidExpenses_20fc87c8-95f5-4884-8340-8a2799b32d92" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxLiabilitiesPrepaidExpenses"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_e5d6dadf-5627-4aeb-8d26-d884dd3576ed" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesPrepaidExpenses_20fc87c8-95f5-4884-8340-8a2799b32d92" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesUndistributedForeignEarnings_76e84339-5cd0-448b-b7a4-a99dcb17f04f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxLiabilitiesUndistributedForeignEarnings"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_e5d6dadf-5627-4aeb-8d26-d884dd3576ed" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesUndistributedForeignEarnings_76e84339-5cd0-448b-b7a4-a99dcb17f04f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesDerivatives_43064746-d5af-4643-b928-8f61ada7f5f1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxLiabilitiesDerivatives"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_e5d6dadf-5627-4aeb-8d26-d884dd3576ed" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesDerivatives_43064746-d5af-4643-b928-8f61ada7f5f1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesOther_d02ff297-f44a-48bb-9c59-db7eaba723e4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxLiabilitiesOther"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities_e5d6dadf-5627-4aeb-8d26-d884dd3576ed" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesOther_d02ff297-f44a-48bb-9c59-db7eaba723e4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsNet_9d90e575-6930-4d5b-bfc3-89f833cc3622" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsNet"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance_d60dca8c-7432-4f64-925b-270951313ee8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsValuationAllowance"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_9d90e575-6930-4d5b-bfc3-89f833cc3622" xlink:to="loc_us-gaap_DeferredTaxAssetsValuationAllowance_d60dca8c-7432-4f64-925b-270951313ee8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsGross_f6e36936-80e7-4902-957f-be7f83615490" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsGross"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsNet_9d90e575-6930-4d5b-bfc3-89f833cc3622" xlink:to="loc_us-gaap_DeferredTaxAssetsGross_f6e36936-80e7-4902-957f-be7f83615490" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxLiabilities_94443f4c-7bba-44ed-b24e-68233bbb36d6" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxLiabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsNet_51739e10-ced5-4e13-94be-7afcdf2a1cd5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsNet"/>
    <link:calculationArc order="1" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_94443f4c-7bba-44ed-b24e-68233bbb36d6" xlink:to="loc_us-gaap_DeferredTaxAssetsNet_51739e10-ced5-4e13-94be-7afcdf2a1cd5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilities_de468fb2-a4b5-42ef-9ba3-872ab0710103" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredIncomeTaxLiabilities"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxLiabilities_94443f4c-7bba-44ed-b24e-68233bbb36d6" xlink:to="loc_us-gaap_DeferredIncomeTaxLiabilities_de468fb2-a4b5-42ef-9ba3-872ab0710103" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsGross"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_144540e1-83ff-4a22-a259-d6efcc4349c5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsOther_144540e1-83ff-4a22-a259-d6efcc4349c5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsHedgingTransactions_538218fa-b88b-4d05-b061-5569d2b0612c" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsHedgingTransactions"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsHedgingTransactions_538218fa-b88b-4d05-b061-5569d2b0612c" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities_e3d7bf61-ed33-4558-9828-39f4274e98d2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities_e3d7bf61-ed33-4558-9828-39f4274e98d2" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_DeferredTaxAssetsLeases_1af05877-ab84-4abb-aff6-c284ad2ed759" xlink:href="int-20211231.xsd#int_DeferredTaxAssetsLeases"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_int_DeferredTaxAssetsLeases_1af05877-ab84-4abb-aff6-c284ad2ed759" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts_b135852f-1c23-4be5-b634-5ebd9cf856cb" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAllowanceForDoubtfulAccounts_b135852f-1c23-4be5-b634-5ebd9cf856cb" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation_28da632a-41b7-433c-b8ad-4a53f79c08dd" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeCompensation_28da632a-41b7-433c-b8ad-4a53f79c08dd" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign_6f986571-c38d-4b76-9d50-3c92851cfc98" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign"/>
    <link:calculationArc order="7" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsForeign_6f986571-c38d-4b76-9d50-3c92851cfc98" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsUnrealizedCurrencyLosses_c05d7669-49f0-4473-a37e-9d6a9bab5767" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsUnrealizedCurrencyLosses"/>
    <link:calculationArc order="8" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsUnrealizedCurrencyLosses_c05d7669-49f0-4473-a37e-9d6a9bab5767" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_7e1037be-1eb0-47e4-ad3b-b89261f5d05b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards"/>
    <link:calculationArc order="9" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_7e1037be-1eb0-47e4-ad3b-b89261f5d05b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_DeferredTaxAssetsInterestLimitation_84f5fdff-af52-454e-abc2-60af8e6e68b8" xlink:href="int-20211231.xsd#int_DeferredTaxAssetsInterestLimitation"/>
    <link:calculationArc order="10" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_int_DeferredTaxAssetsInterestLimitation_84f5fdff-af52-454e-abc2-60af8e6e68b8" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_DeferredTaxAssetsDerivatives_5885472b-9edb-496a-bb7f-df81d391c5b4" xlink:href="int-20211231.xsd#int_DeferredTaxAssetsDerivatives"/>
    <link:calculationArc order="11" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_int_DeferredTaxAssetsDerivatives_5885472b-9edb-496a-bb7f-df81d391c5b4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_DeferredTaxAssetsInstallmentSale_385f5753-9957-4b75-9899-6d8a81b9ea42" xlink:href="int-20211231.xsd#int_DeferredTaxAssetsInstallmentSale"/>
    <link:calculationArc order="12" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_int_DeferredTaxAssetsInstallmentSale_385f5753-9957-4b75-9899-6d8a81b9ea42" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_int_DeferredTaxAssetsCustomerDeposits_2faf3561-0039-4784-81cd-7c7a0b97aa20" xlink:href="int-20211231.xsd#int_DeferredTaxAssetsCustomerDeposits"/>
    <link:calculationArc order="13" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsGross_60d0130d-1c17-41f0-b9ef-3ce793d91bf8" xlink:to="loc_int_DeferredTaxAssetsCustomerDeposits_2faf3561-0039-4784-81cd-7c7a0b97aa20" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/IncomeTaxesNetOperatingLossesandIncomeTaxConcessionsDetails" xlink:type="simple" xlink:href="int-20211231.xsd#IncomeTaxesNetOperatingLossesandIncomeTaxConcessionsDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/IncomeTaxesNetOperatingLossesandIncomeTaxConcessionsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_b0f54fe3-75d4-48b0-a5a1-965b67327cd1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsForeign_80c3dc1b-31b1-416b-903e-5b6e21f79994" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsForeign"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_b0f54fe3-75d4-48b0-a5a1-965b67327cd1" xlink:to="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsForeign_80c3dc1b-31b1-416b-903e-5b6e21f79994" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsDomestic_c80cba69-237c-40d3-8aeb-2f7c4a2b640e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsDomestic"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_b0f54fe3-75d4-48b0-a5a1-965b67327cd1" xlink:to="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsDomestic_c80cba69-237c-40d3-8aeb-2f7c4a2b640e" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/FairValueMeasurementsAssetsandLiabilitiesDetails" xlink:type="simple" xlink:href="int-20211231.xsd#FairValueMeasurementsAssetsandLiabilitiesDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/FairValueMeasurementsAssetsandLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_4d93444f-334f-43ab-91e6-ed3947618cd8" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_8487ca64-ae67-49f7-9a0f-8b826f7cf7d4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeAsset"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_4d93444f-334f-43ab-91e6-ed3947618cd8" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_8487ca64-ae67-49f7-9a0f-8b826f7cf7d4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsFairValueDisclosure_c0825062-f7d1-46f2-92e4-0cbe2b0e1eba" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_InvestmentsFairValueDisclosure"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsFairValueDisclosure_4d93444f-334f-43ab-91e6-ed3947618cd8" xlink:to="loc_us-gaap_InvestmentsFairValueDisclosure_c0825062-f7d1-46f2-92e4-0cbe2b0e1eba" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_8503a220-09c7-46b3-bda7-9aba9cf6c3e2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosure"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_4e4b400b-a195-408c-a9ea-93c0eb959981" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure_8503a220-09c7-46b3-bda7-9aba9cf6c3e2" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_4e4b400b-a195-408c-a9ea-93c0eb959981" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/FairValueMeasurementsCommodityandForeignCurrencyContractsDetails" xlink:type="simple" xlink:href="int-20211231.xsd#FairValueMeasurementsCommodityandForeignCurrencyContractsDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/FairValueMeasurementsCommodityandForeignCurrencyContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_3d7a429b-8aac-45f8-b958-2810d8acebaf" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeLiabilities"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_956ecc1d-9ed3-41e3-8c9a-ed04f9f09754" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeLiabilities_3d7a429b-8aac-45f8-b958-2810d8acebaf" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_956ecc1d-9ed3-41e3-8c9a-ed04f9f09754" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityFairValueGrossAsset_770f7177-826c-4a0c-b36f-f58a70c32403" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeLiabilityFairValueGrossAsset"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeLiabilities_3d7a429b-8aac-45f8-b958-2810d8acebaf" xlink:to="loc_us-gaap_DerivativeLiabilityFairValueGrossAsset_770f7177-826c-4a0c-b36f-f58a70c32403" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_fe9e3013-2b55-400f-8394-7397c7cf5135" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_518e1824-1d84-4f7e-8e7b-436ecc6d07aa" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeLiabilities"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_fe9e3013-2b55-400f-8394-7397c7cf5135" xlink:to="loc_us-gaap_DerivativeLiabilities_518e1824-1d84-4f7e-8e7b-436ecc6d07aa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeCollateralRightToReclaimCash_70b0848a-d938-4107-aefd-a25646c4a7d9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeCollateralRightToReclaimCash"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_fe9e3013-2b55-400f-8394-7397c7cf5135" xlink:to="loc_us-gaap_DerivativeCollateralRightToReclaimCash_70b0848a-d938-4107-aefd-a25646c4a7d9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangementDeduction_5e79dc4e-82e7-4094-b7dc-764ac450e0c5" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangementDeduction"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeLiabilityFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_fe9e3013-2b55-400f-8394-7397c7cf5135" xlink:to="loc_us-gaap_DerivativeLiabilityNotSubjectToMasterNettingArrangementDeduction_5e79dc4e-82e7-4094-b7dc-764ac450e0c5" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_02577c6c-3a69-4f21-852d-5c6ffd41a9bd" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeAssets"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_49f3a749-aff7-4757-94f5-835e34765908" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeAsset"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeAssets_02577c6c-3a69-4f21-852d-5c6ffd41a9bd" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_49f3a749-aff7-4757-94f5-835e34765908" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueGrossLiability_7adcd5af-a6b8-4db7-8d63-45756621e5e9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeAssetFairValueGrossLiability"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeAssets_02577c6c-3a69-4f21-852d-5c6ffd41a9bd" xlink:to="loc_us-gaap_DerivativeAssetFairValueGrossLiability_7adcd5af-a6b8-4db7-8d63-45756621e5e9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_290455aa-a778-433f-8bf9-93af71a3854d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssets_0f05a676-5458-47b4-aeb2-c24e4f9a051e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeAssets"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_290455aa-a778-433f-8bf9-93af71a3854d" xlink:to="loc_us-gaap_DerivativeAssets_0f05a676-5458-47b4-aeb2-c24e4f9a051e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeCollateralObligationToReturnCash_66f19a3c-12ef-41fe-bdbb-5e1daad46451" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeCollateralObligationToReturnCash"/>
    <link:calculationArc order="2" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_290455aa-a778-433f-8bf9-93af71a3854d" xlink:to="loc_us-gaap_DerivativeCollateralObligationToReturnCash_66f19a3c-12ef-41fe-bdbb-5e1daad46451" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangementDeduction_81e8408b-cffb-4522-8d96-30e45bdecb93" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangementDeduction"/>
    <link:calculationArc order="3" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DerivativeAssetFairValueOffsetAgainstCollateralNetOfNotSubjectToMasterNettingArrangementPolicyElection_290455aa-a778-433f-8bf9-93af71a3854d" xlink:to="loc_us-gaap_DerivativeAssetNotSubjectToMasterNettingArrangementDeduction_81e8408b-cffb-4522-8d96-30e45bdecb93" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/RevenuefromContractswithCustomersDetails" xlink:type="simple" xlink:href="int-20211231.xsd#RevenuefromContractswithCustomersDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/RevenuefromContractswithCustomersDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_db914284-2c6a-4c22-a6be-35d5a958cebd" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_Revenues"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_201554f0-9584-4003-b268-66c8b19aeb1b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Revenues_db914284-2c6a-4c22-a6be-35d5a958cebd" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_201554f0-9584-4003-b268-66c8b19aeb1b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueNotFromContractWithCustomer_ca65553b-1657-481d-b756-57b1ec120aa0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_RevenueNotFromContractWithCustomer"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Revenues_db914284-2c6a-4c22-a6be-35d5a958cebd" xlink:to="loc_us-gaap_RevenueNotFromContractWithCustomer_ca65553b-1657-481d-b756-57b1ec120aa0" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/LeasesLeaseCostDetails" xlink:type="simple" xlink:href="int-20211231.xsd#LeasesLeaseCostDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/LeasesLeaseCostDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseCost_b74160d6-90e0-43fe-9778-dda1477af65b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LeaseCost"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseRightOfUseAssetAmortization_ca167c9f-9998-47e7-be5d-e63a8fda017e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseRightOfUseAssetAmortization"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_b74160d6-90e0-43fe-9778-dda1477af65b" xlink:to="loc_us-gaap_FinanceLeaseRightOfUseAssetAmortization_ca167c9f-9998-47e7-be5d-e63a8fda017e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseInterestExpense_72a1d307-05ed-4c30-a812-c5a2f49b0ad4" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseInterestExpense"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_b74160d6-90e0-43fe-9778-dda1477af65b" xlink:to="loc_us-gaap_FinanceLeaseInterestExpense_72a1d307-05ed-4c30-a812-c5a2f49b0ad4" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseCost_a9a0380a-6805-4038-8423-b495811a5ac9" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingLeaseCost"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_b74160d6-90e0-43fe-9778-dda1477af65b" xlink:to="loc_us-gaap_OperatingLeaseCost_a9a0380a-6805-4038-8423-b495811a5ac9" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShortTermLeaseCost_f1767fa6-dc63-4e9e-8782-96f24ef5705d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_ShortTermLeaseCost"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_b74160d6-90e0-43fe-9778-dda1477af65b" xlink:to="loc_us-gaap_ShortTermLeaseCost_f1767fa6-dc63-4e9e-8782-96f24ef5705d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableLeaseCost_fc5c230d-366b-435d-9c12-bdb92dbf00aa" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_VariableLeaseCost"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_b74160d6-90e0-43fe-9778-dda1477af65b" xlink:to="loc_us-gaap_VariableLeaseCost_fc5c230d-366b-435d-9c12-bdb92dbf00aa" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubleaseIncome_f1ddf1d9-5976-4cb4-b644-79d80ebd893b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_SubleaseIncome"/>
    <link:calculationArc order="6" weight="-1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LeaseCost_b74160d6-90e0-43fe-9778-dda1477af65b" xlink:to="loc_us-gaap_SubleaseIncome_f1ddf1d9-5976-4cb4-b644-79d80ebd893b" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/LeasesRemainingLeasePaymentsDetails" xlink:type="simple" xlink:href="int-20211231.xsd#LeasesRemainingLeasePaymentsDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/LeasesRemainingLeasePaymentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1dc456d5-0b67-487f-96d5-95f38fc305ed" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_4e7e8782-a1f9-4ad5-a880-a4debda4828f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1dc456d5-0b67-487f-96d5-95f38fc305ed" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_4e7e8782-a1f9-4ad5-a880-a4debda4828f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLeaseLiability_d696807c-21a3-4d18-a8c0-a5982290f59d" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_OperatingLeaseLiability"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1dc456d5-0b67-487f-96d5-95f38fc305ed" xlink:to="loc_us-gaap_OperatingLeaseLiability_d696807c-21a3-4d18-a8c0-a5982290f59d" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_d8cd7965-d42e-4832-a726-a1f37fc3d801" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths_306978f4-7a0e-4a4d-9642-7ac03ad23b15" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_d8cd7965-d42e-4832-a726-a1f37fc3d801" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueNextTwelveMonths_306978f4-7a0e-4a4d-9642-7ac03ad23b15" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo_08bd633b-240d-4ac8-b488-22087be1f21f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_d8cd7965-d42e-4832-a726-a1f37fc3d801" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearTwo_08bd633b-240d-4ac8-b488-22087be1f21f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree_10281535-587e-4e2c-8b46-f248216b54be" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_d8cd7965-d42e-4832-a726-a1f37fc3d801" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearThree_10281535-587e-4e2c-8b46-f248216b54be" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour_84206ea7-b162-41b5-8ee0-8b1dce5546b7" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_d8cd7965-d42e-4832-a726-a1f37fc3d801" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearFour_84206ea7-b162-41b5-8ee0-8b1dce5546b7" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearFive_766c2203-9c15-4e83-bb5a-6477d159bd8f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueYearFive"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_d8cd7965-d42e-4832-a726-a1f37fc3d801" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueYearFive_766c2203-9c15-4e83-bb5a-6477d159bd8f" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueAfterYearFive_0bb14fbd-48c5-4193-95fe-4840aea97672" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDueAfterYearFive"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_d8cd7965-d42e-4832-a726-a1f37fc3d801" xlink:to="loc_us-gaap_FinanceLeaseLiabilityPaymentsDueAfterYearFive_0bb14fbd-48c5-4193-95fe-4840aea97672" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/LeasesRemainingLeasePaymentsDetails_1" xlink:type="simple" xlink:href="int-20211231.xsd#LeasesRemainingLeasePaymentsDetails_1"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/LeasesRemainingLeasePaymentsDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_3a2c1c43-8d80-4f69-917f-d890e3513d6e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_991ec8e6-6a30-46ec-a228-94286840c51b" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_3a2c1c43-8d80-4f69-917f-d890e3513d6e" xlink:to="loc_us-gaap_FinanceLeaseLiabilityUndiscountedExcessAmount_991ec8e6-6a30-46ec-a228-94286840c51b" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinanceLeaseLiability_e326d970-1e6a-401c-86cb-0c3896c433e0" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_FinanceLeaseLiability"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FinanceLeaseLiabilityPaymentsDue_3a2c1c43-8d80-4f69-917f-d890e3513d6e" xlink:to="loc_us-gaap_FinanceLeaseLiability_e326d970-1e6a-401c-86cb-0c3896c433e0" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1e422f0c-40f3-4f85-a445-0ac9bdd16598" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_1aa6e1e1-db10-4f79-8552-079905ffb241" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1e422f0c-40f3-4f85-a445-0ac9bdd16598" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_1aa6e1e1-db10-4f79-8552-079905ffb241" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_17625323-3cc9-4e3d-94dd-40c38034214e" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1e422f0c-40f3-4f85-a445-0ac9bdd16598" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_17625323-3cc9-4e3d-94dd-40c38034214e" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_5b216aa3-252f-4678-80b8-5e98abbf14f1" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree"/>
    <link:calculationArc order="3" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1e422f0c-40f3-4f85-a445-0ac9bdd16598" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_5b216aa3-252f-4678-80b8-5e98abbf14f1" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_ca507665-d06a-4424-8918-b98b18f87abc" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour"/>
    <link:calculationArc order="4" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1e422f0c-40f3-4f85-a445-0ac9bdd16598" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_ca507665-d06a-4424-8918-b98b18f87abc" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_fa74b66a-6034-4df6-ae4c-a6be269e6f99" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive"/>
    <link:calculationArc order="5" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1e422f0c-40f3-4f85-a445-0ac9bdd16598" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive_fa74b66a-6034-4df6-ae4c-a6be269e6f99" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_309e1184-0e1a-4d3b-bfb3-a9689a50b5a2" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive"/>
    <link:calculationArc order="6" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1e422f0c-40f3-4f85-a445-0ac9bdd16598" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive_309e1184-0e1a-4d3b-bfb3-a9689a50b5a2" xlink:type="arc"/>
  </link:calculationLink>
  <link:roleRef roleURI="http://www.wfscorp.com/role/EarningsperCommonShareDetails" xlink:type="simple" xlink:href="int-20211231.xsd#EarningsperCommonShareDetails"/>
  <link:calculationLink xlink:role="http://www.wfscorp.com/role/EarningsperCommonShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_bf3d1f06-a6c2-4cff-ba4d-d9a604602cdf" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_b3af0c9e-9179-4f71-ae45-fa1c0d1dc792" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:calculationArc order="1" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_bf3d1f06-a6c2-4cff-ba4d-d9a604602cdf" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_b3af0c9e-9179-4f71-ae45-fa1c0d1dc792" xlink:type="arc"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_3d1bb083-7f2d-4e93-ba1b-66b246ca750f" xlink:href="https://xbrl.fasb.org/us-gaap/2021/elts/us-gaap-2021-01-31.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment"/>
    <link:calculationArc order="2" weight="1.0" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_bf3d1f06-a6c2-4cff-ba4d-d9a604602cdf" xlink:to="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_3d1bb083-7f2d-4e93-ba1b-66b246ca750f" xlink:type="arc"/>
  </link:calculationLink>
</link:linkbase>
