关税传递和进口再分配（英）

TariffPass-ThroughandImportReallocation

JaeBinAhn,LorenzoRotunno,andMicheleRuta

WP/26/149

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representtheviewsoftheIMF,itsExecutiveBoard,orIMFmanagement.

2026JUL

©2026InternationalMonetaryFundWP/26/149

IMFWorkingPaper

Strategy,PolicyandReviewDepartment&WesternHemisphereDepartment

TariffPass-ThroughandImportReallocation

AuthorizedfordistributionbyNigelChalkandDariaZakharova

July2026

IMFWorkingPapersdescriberesearchinprogressbytheauthor(s)andarepublishedtoelicit

commentsandtoencouragedebate.TheviewsexpressedinIMFWorkingPapersarethoseofthe

author(s)anddonotnecessarilyrepresenttheviewsoftheIMF,itsExecutiveBoard,orIMFmanagement.

ABSTRACT:WestudyhowU.S.tariffhikesin2025havetransmittedtoimportprices.Consistentwithrecentevidence,wefindthatduty-exclusiveimportpricesatthevariety(country-product)leveldonotadjusttotariffs,implyingfullpass-throughtoduty-inclusivepricesattheborder.Attheproductlevel,however,duty-exclusiveaggregateimportpricesdeclinesignificantlywithtariffincreases.Weshowthatthisproduct-leveldeclineisdrivenbywithin-productreallocationtowardlower-pricedsources—strongerinproductsfacinglargertariffhikes—andoperatesprimarilythroughtheentryoflower-pricedvarietiesandtheexitofhigher-pricedones.Estimatesofvarietyappealindicatethatpartofthisreallocationreflectsshiftstowardlower-qualityvarieties,achannelthatisalsopresentinthe2018–19U.S.–Chinatariffepisode.Thesereallocationeffectscarryimplicationsforconsumerwelfareandproductivitythroughthequalityofimportedgoodsandinputs.

RECOMMENDEDCITATION:Ahn,J.,Rotunno,L.,andRuta,M.(2026).TariffPass-ThroughandImportReallocation.IMFWorkingPaperWP/26/149.InternationalMonetaryFund.

JELClassificationNumbers:

F13;F14

Keywords:

Tariffpass-through:imports:reallocation:productappeal.

Author’sE-MailAddress:

jahn@;lrotunno@;mruta@

1

TariffPass-ThroughandImportReallocation*

JaeBinAhn†LorenzoRotunno‡MicheleRuta§

July17,2026

Abstract

WestudyhowU.S.tariffhikesin2025havetransmittedtoimportprices.Consistentwithrecentevidence,wefindthatduty-exclusiveimportpricesatthevariety(country-product)leveldonotadjusttotariffs,implyingfullpass-throughtoduty-inclusivepricesattheborder.Attheproductlevel,however,duty-exclusiveaggregateimportpricesdeclinesignificantlywithtariffincreases.Weshowthatthisproduct-leveldeclineisdrivenbywithin-productre-allocationtowardlower-pricedsources—strongerinproductsfacinglargertariffhikes—andoperatesprimarilythroughtheentryoflower-pricedvarietiesandtheexitofhigher-pricedones.Estimatesofvarietyappealindicatethatpartofthisreallocationreflectsshiftstowardlower-qualityvarieties,achannelthatisalsopresentinthe2018–19U.S.–Chinatariffepisode.Thesereallocationeffectscarryimplicationsforconsumerwelfareandproductivitythroughthequalityofimportedgoodsandinputs.

Keywords:Tariffpass-through,imports,reallocation,productappeal.

JELcodes:F13,F14.

*TheauthorswouldliketothankMaryAmiti,NigelChalk,GeorgeCui,GitaGopinath,MohammadKhabbazan,FernandoLeibovici,BrentNeiman,JeongwonSon,DavidWeinstein,andtheseminarparticipantsattheInternationalMonetaryFundforhelpfulsuggestions.

†InternationalMonetaryFund.E-mail:jahn@imf.org

‡InternationalMonetaryFund.E-mail:lrotunno@imf.org

§InternationalMonetaryFund.E-mail:mruta@imf.org

2

1Introduction

RecentU.S.tariffactionshavesparkedintenseacademicandpolicydebateregardingtheireco-nomicimplicationsfortheU.S.anditstradingpartners.Acentralpolicyquestionconcernstheincidenceofthesetariffs—namely,whoultimatelybearstheircost—andhowthisincidencetrans-latesintoinflationarypressureswithintheU.S.economy.Addressingthisissuerequiresexamin-inghowtariffsaffectexporters’pricesattheborderandtheextenttowhichthesecostchangespassthroughtoimportprices,domesticproducerprices,andultimatelyconsumerprices.Inpractice,tariffincidenceanditsinflationaryimpactdependonseveralinteractingmechanisms,includ-ingthedegreeofborderpass-through,marketstructureandpricingbehavioralongglobalvaluechains,andthereallocationoftradeflowsacrossforeignanddomesticsuppliers.Understandingthesechannelsisessentialforassessingwhethertariffsgeneratesustainedinflationarypressuresorwhethertheireffectsaremitigatedthroughadjustmentsinsourcing,markups,orinternationalpricesetting.Itisalsokeytounderstandingthebroadereffectsofthetariffsonproductivityandwelfare.

Thispaperestimatestariffpass-throughintoU.S.importunitvaluesattwolevels:themostde-tailed‘variety’level(exporter-HS10-digitproductcombinations)andthe‘product’(HS10-digit)level.Thevariety-levelanalysisidentifiespass-throughtoexporters’prices(proxiedbyimportunitvaluesexcludingduties)andfollowsthestandardapproachintheliterature.Theproduct-levelanalysiscombinestariffeffectsonexporters’priceswithshiftsinsourcingacrossorigincoun-triesforagivenproduct.Thisapproachclarifieshowtariff-inducedimportreallocationshapesimportpricesand,inturn,informstheincidencedebate.

1

Additionally,weinvestigatehowthereallocationaffectsthequalityofU.S.imports,whichisacrucialingredienttoassesstheimplica-tionsforwelfareandproductivity.

OurempiricalanalysisusesmonthlyU.S.Censusdataonimportsandcollectedduties.ThedatareportimportvaluesandquantitiesbycountryoforiginandHS10-digitproduct.Wemea-surevariety-levelpricesusingunitvalues,bothexcludingcollectedduties(duty-exclusiveorex-porters’prices)andincludingduties(duty-inclusiveorafter-tariffimportprices),allonanFOB(freeonboard)basis.Atthesamelevelofobservation,wedefinetheeffectivetariffrateascol-lecteddutiesdividedbyimportvalues—thatis,thetariffprotectioneffectivelyfacedbyimporters

1Thetradeliteratureoftendefinestariffpass-throughatthevarietylevel.Weadditionallyemphasizepass-throughmeasuredusingproduct-levelaggregateprices,whicharerelevantobjectsfordomesticinflation.Product-levelpass-throughcaptureswithin-varietypriceresponsesaswellaschangesinimportcompositionacrossvarieties.

3

andexportersatU.S.customs.

Inthebaselinespecification,weregressyear-on-yearmonthlychangesinU.S.importprices,val-ues,andquantitiesonchangesinU.S.importtariffsovertheperiodfromFebruary2025—whentheU.S.administrationbeganmateriallyrevisingtariffpolicy—throughDecember2025.Year-on-yeardifferencingremovesseasonality,andmonthlytariffvariationcaptureshigh-frequencypol-icychangeswithintheperiod,includingbothtariffincreasesanddecreases.Westudyresponsesalongtheintensivemarginusingoutcomevariablesinlogchanges,andalongtheextensivemar-ginusingentryandexitdummiesforU.S.importvarieties.

Ourpreferredestimatesrelyonatwo-stageleastsquaresapproachthatinstrumentseffectivetariffrateswithstatutoryU.S.tariffs.WedrawstatutorytariffdatafromtheWTO-IMFTariffTracker(

WTO-IMF

,

2026

),availablebytradingpartnerattheHS8-digitlevel.Asdocumentedby

GopinathandNeiman

(

2026

),wenoteawideninggapbetweeneffectiveandstatutoryrates,partlydrivenbybehavioralresponses.Althougheffectivetariffscapturepolicyasimplementedattheborder,theyarepotentiallyendogenousbecausetheratioofcollecteddutiestoimportval-uescanmovewithimportresponses,generatingreversecausality.Statutorytariffs,bycontrast,identifypolicy-drivenvariationineffectivetariffsandthereforecanserveasavalidinstrument(

FajgelbaumandKhandelwal

,

2026

).

Ourfirstsetoffindingsalignswithrecentevidencethatexporters’pricesrespondlittletoU.S.tar-iffs,andthatthesetariffspromotereallocationofimportsacrosstradingpartners.Atthevarietylevel,importpricesinclusiveofcollecteddutiesriseone-to-onewithtariffs,whileimportvaluesandquantitiesdeclinesignificantly.Ourestimatessuggestthatan8percentagepointincreaseintheeffectiveU.S.tariffrate—similartotheriseobservedbetweenFebruaryandDecember2025—impliesanaverageimportdeclineofabout3.6percent.Crucially,theseeffectsemergefromvaria-tionintariffchangesacrossvarietiesofthesameimportproduct.Ourresultsindicatesignificantreallocationeffects—importsofvarietieshitbyhighertariffsdecreaserelativetothoseofothervarietiesofthesameproduct.Wealsofindstrongextensive-margineffects:higherstatutoryU.S.tariffsarerobustlyassociatedwithgreaterexitandlowerentryofU.S.importvarietieswithinaproduct.

Thissubstantialreallocationofimportsacrosstradingpartnersinfluenceshowtariffsaffectproduct-levelimportprices.Wefindthatimportpricesexcludingcollecteddutiesfallsignificantlywithincreasesintheaverageproduct-levelU.S.effectivetariffs—astrikingcontrastwiththemutedef-

4

fectatthevarietylevel.Tounpackthisresult,weimplementadecompositionexercisethatisolatesthecontributionofdistinctmargins.Crucially,itshowshowadjustmentoccursthroughboththeintensivemargin(pricesofcontinuingvarieties)andtheextensivemargin(pricesofenteringandexitingvarieties).

Ourestimationresultshighlightanovelmechanismthroughwhichtariffsaffectimportprices.TheestimatessuggestthatthestrongnegativeeffectofU.S.tariffsonproduct-levelimportpricesisdrivenlargelybyreallocationfromhigher-pricedtolower-pricedvarieties,particularlythroughextensive-marginadjustments.Whiletheestimatesindicatea(relativelysmall)negativeeffectofU.S.tariffchangesonproduct-levelaveragepricesamongincumbentvarieties,theyrevealthatnewlyenteringvarietiesaresignificantlycheaper,withthepatternbeingmorepronouncedinproductsfacinglargerU.S.tariffincreases.Similarly,theexitofhigher-pricedvarietiesisstrongerinproductswithlargertariffhikes.Together,theseeffectscontributetothenegativeassociationbetweentariffsandpre-tariffproduct-levelimportprices,apatternthatwasalsoevidentduringthe2018-19U.S.tariffepisode.

Suchashifttowardlower-pricedsourcingraisesthequestionofwhythiscost-reducingreallo-cationintensifieswithhighertariffs.Twomechanismscouldbeatplay,possiblyatthesametime:efficiencyversusquality.Onepossibilityisthattheunprecedentedtariffincreasesinducedimporterstoincursubstantialfixedcostsofsearchingforalternative,moreefficientsuppliers,whereastheincentivestoadjustsourcingareweakerwithlowertariffs.

2

Asecondpossibilityis

thatthereallocationtowardlower-pricedvarietiesmayentailshiftstowardvarietieswithlower“appeal”(

ReddingandWeinstein

,

2020

,

2024

),reflectinglowerqualityorweakerconsumerpref-erences.

Togaugetherelativeimportanceofthesetwochannels,wecomparetheestimatedtariffeffectsonproduct-levelpriceindexesconstructedwithandwithoutadjustmentsforvariety-levelap-peal.Specifically,weestimatethevariety-specificappealwithinaCESdemandframework,whereappealactsasademandshifter:varietiesthatcommandhigherimportsharesdespitehigherunitpricesareassignedhigherestimatedappeal(

ReddingandWeinstein

,

2020

;

Khandelwal

,

2010

).Appealcapturesacombinationofqualitydifferencesandpreferenceheterogeneity.To

2See

Alfaroetal.

(

2025

)fordirectevidenceofcostlyreallocationofU.S.importsacrosssuppliers,and

Benguriaand

Saffie

(

2024

)forU.S.exportsacrossdestinations,duringthe2018-19U.S.-Chinatariffepisode.Thisinterpretationisconsistentwithmodelsofinternationalsourcingwithcostlysearchandmatchingfrictionsinbuyer–supplierrelation-ships,whichcangeneratediscreteextensive-marginadjustmentswhenincentivesbecomesufficientlystrong(e.g.,

Ahn

andTan

,

2025

).

5

facilitateidentification,weestimateappealusingpre-perioddatafrom2023–24andtreatitastime-invariant.Consequently,changesinimport-weightedappealattheHS10-digitproductlevelarisesolelyfromreallocationacrosssourcecountries.Asasecondstep,todistinguishbe-tweencompositionaleffectsassociatedwithchangesinappeal(e.g.,qualitydowngrading)andgenuinepricemovementsnetofappeal,weconstructamodel-consistent,appeal-adjustedpriceindexattheHS10-digitlevelbasedontheCESunit-expenditurefunction.Thisindexaggregatesexporter-levelpriceswithinaproduct,weightingeachvarietybyitsestimatedappeal,andthuscaptureswithin-productvariationinpricesexpressedinutility-equivalentunits.Differencesintheproduct-levelCESpriceindexesovertimecaptureadjustmentsalongboththeintensiveandextensivemargins.

Regressionresultsusingthisappeal-adjustedCESpriceindexshowthatthetariff-induceddeclineinproduct-levelpricesisweakerthantheoneobtainedusingunadjustednominalpriceindexes.Thisfindingindicatesthattheobserveddeclineinnominalproduct-levelimportpricesisnotdrivensolelybyanefficientreallocationtowardlower-costsources,butalsoreflectstherealloca-tiontowardlower-appealvarieties.

UsingtheCESpriceindexconstructedfromduty-inclusiveimportpricesfurtherunderscorestheimportanceofaccountingfortheappealofdifferentvarieties.Withunadjustednominalproduct-levelCESprices,wefindthattariffchangeshaveanegligibleor,in2018-19,evennegativeeffectontariff-inclusiveprices.Thisseeminglycounterintuiveresulthoweverchangeswhenweuseappeal-adjustedprices:wefindthatappeal-adjustedduty-inclusiveCESimportpricesincreasesignificantlywithproduct-levelU.S.tariffs,albeitlessthanone-for-one.ThesepatternssuggestthatthelowerimportpricesinproductshitbyhigherU.S.tariffsreflectreallocationtowardva-rietieswithlowerappeal.

3

Overall,theseresultssuggestthatthereallocationofimportstowardlower-qualityvarietiesinresponsetotariffhikescouldhaveamaterialeffectonwelfareandpro-ductivity(e.g.,throughareductionofthequalityofimportedinputs).

Ourmaincontributionistolinktheeffectsoftariffsontradereallocationtotheireffectsonimportprices.Model-basedandeconometricworkshowsthatU.S.tariffsin2018-19andagainin2025

3Consistentwiththischannel,a2026surveyofover200U.S.andCanadianmanufacturingqualityleadersfindsthat

62percentreportthattariffsandtradebarriershavemadeithardertomaintainproductqualityoverall(

Lumafield

,

2026

).Inapparel,forexample,reportingbasedonQIMAfactory-inspectiondataattributesarecentriseinfailurerates—–theshareofshipmentswithtoomanydefectstoreachmarket—inparttosupplychainsrelocatingawayfromChinainresponsetotariffs,towarddestinations,suchasIndiaandCambodia,thatexhibithigherfailureratesthanChinaitself(

NBCNews

,

2025

).

6

shiftedU.S.importsawayfromhighlytariffedsources(notablyChinain2018-19)towardalter-nativesuppliers(

FajgelbaumandKhandelwal

,

2026

;

RotunnoandRuta

,

2026

;

Fajgelbaumetal.

,

2024

;

CaliendoandParro

,

2022

).Thesameliteraturefindslimitedpass-throughofU.S.tariffsintoexporters’pricesinbothepisodes(

GopinathandNeiman

,

2026

;

Amitietal.

,

2026

;

Hinzetal.

,

2026

;

FajgelbaumandKhandelwal

,

2026

;

Fajgelbaumetal.

,

2020

;

Amiti,ReddingandWeinstein

,

2020

),althoughtransaction-leveleconomiesofscalesuggestthatexportersmayabsorbalargershareofthetariffthroughlowerpricesasshipmentvolumesdecline(

GanapatiandHottman

,

2026

).

4

Weconfirmthesefindingsandaddthattariffscanlowerproduct-levelpre-tariffimportpricesthroughcompositionalshiftstowardlower-pricedvarieties,evenwhenexporters’pricesatthevarietylevelremainunchanged.

5

AmongrecentpapersstudyingthepriceeffectsofU.S.tariffs,

Chinagorom-AbiakalamandLei-

bovici

(

2025

,

2026

)studyaggregateimportpricedynamicswithoutexplicitlyrelatingthemtotariffvariation.TheyshowthatsincetheFebruary2025tariffround,pre-tariffU.S.importpriceshave,ifanything,increasedslightly.Althoughunitvaluesofindividualvarietiesdeclinedonaverage,aggregateimportsshiftedtowardvarietieswhoseunitpriceshavestrongergrowth.OurresultssuggestthatthevariationofU.S.tariffsacrosstradingpartnersattenuatedthisaggregatepattern:

productsfacinglargertariffincreasesreallocatedrelativelymoretowardlower-pricedvarieties.Importadjustmentsalongtheextensivemargin(e.g.,entryoflower-pricedvarieties)playacru-cialroleinexplainingthisreallocation.

Therestofthepaperisorganizedasfollows.Section

2

describesthedataandpresentsstylizedfactsonstatutoryandeffectiveU.S.tariffs.Section

3

outlinestheempiricalstrategyandreportsresultsforthe2025U.S.tariffhike.Itshowsthefindingsatboththevarietyandproductlevels,withparticularemphasisonthenovelproduct-levelevidence,andtheestimatesoftariffeffectsonproductappeal.Thefollowingsectionreportsadditionalresultsforthe2018-19tariffepisode.Finally,Section

5

summarizesthemainfindingsanddiscussesavenuesforfutureresearch.

4Theabsenceoflargeexporter-priceresponsesincross-sectionalregressionsdoesnotnecessarilycontradictthethe-oreticalpredictionthattheU.S.canexploitmarketpowertoinfluencetermsoftradethroughtariffs(

Caliendoand

Parro

,

2022

;

FajgelbaumandKhandelwal

,

2022

).Terms-of-tradeeffectsareidentifiedingeneralequilibriumquantita-tivetrademodelsandcancounteractwelfarelossesfromconsumptionandproductiondistortionscausedbythetariffs—see

RotunnoandRuta

(

2026

);

Ignatenkoetal.

(

2025

);

Rodríguez-Clareetal.

(

2025

)forapplicationstothe2025tariffepisode.

5Inarecentpaper,

deSouzaetal.

(

2025

)findthatU.S.importingfirmsswitchedtheirsourcingfromsupplierslocatedincountriesfacinghightradepolicyuncertaintytowardthoseinlow-uncertaintysources,intheweeksfollowingtheApril2,2025,tariffannouncement.WedocumentthatU.S.importshavereallocatedacrosssourcesalsoinresponsetoactualtariffchanges.

7

2Dataandstylizedfacts

2.1Data

Theempiricalanalysisusesdetailedproduct-leveltariffandtradedatacovering2024-25.MonthlyU.S.importdatacomefromtheU.S.CensusBureauwhichreportsimportvalues(incurrentUS$),quantities,anddutiesbycountryoforiginandHS10-digitproduct.Wemeasurepricesusingimportunitvalues:valuesexcludingcollecteddutiesdefineFOB(FreeOnBoard)prices,whilevaluesincludingcollecteddutiesdefinetariff-inclusiveunitvalues.

6

Weconsidertwotypesoftariffmeasures:the‘effective’tariffrates,whicharecomputedastheratioofcalculateddutiestothevalueofimportsforconsumption;andthe‘statutory’tariffrates,definedasthetariffsimplementedbytheU.S.administrationthroughofficialdocuments(e.g.,publishedintheFederalRegister).

Whileeffectivetariffratesreflectthetariffsactuallyfacedbyimportersattheborder,theycandeviatefromstatutoryratesforseveralreasons.Theseincludeimplementationpractices,exemp-tionsnotfullycapturedinstatutoryschedules,shipmentlags,andbehavioralresponsestotariffpolicy,suchaschangesintheuseofpreferentialrates.Unlikestatutoryrates,effectiveratesareundefinedwhenthetariffis‘prohibitive’andimportvaluesfalltozero.

Bycontrast,statutorytariffratesmeasurethetradepolicythatpolicymakersintendtoimplementthroughofficiallegalmeasures.WeobtainstatutorytariffratesandtheirtimevariationfromtheWTO-IMFTariffTracker(

WTO-IMF

,

2026

),adatainitiativeaimedattrackingrecenttariffactionsbytheU.S.andrelatedtariffresponsesbytradingpartners.ThedatasetincludestheU.S.tariffsattheHS8-digitleveltogetherwiththeirdailydateofimplementation,asdocumentedinofficialregulationsandlegislation.

Twoadjustmentsareappliedtobetterreflecttheprescribedimplementationofthesetariffs(see

WTO-IMF

(

2026

)).First,theU.S.tariffsonCanadaandMexicoarescaleddownproportionallytotheobservedUSMCApreferenceutilizationrateattheproductlevel—updatedwithalagofafewmonths—toproxyforUSMCAeligibility,aconditionforexemptionfromtheU.S.importtariffs.

7

6Specifically,wecalculatetheFOBimportunitpriceastheratioofthetotalcustomsvalueofimportsforconsump-tiontotheirphysicalvolume,whiletheduty-inclusiveunitpriceaddstheestimatesofcalculateddutytothenumerator.Althoughstandardintheempiricalliterature(e.g.,

Fajgelbaumetal.

,

2020

;

FajgelbaumandKhandelwal

,

2022

;

Amiti,

ReddingandWeinstein

,

2020

),thisapproachcanmaskvariationinpricingstrategiesacrossfirmsexportingthesameHS10-digitproductfromagivencountry.

7AsofFebruary2026,theUSMCApreferenceutilizationrateswerecalculatedusingU.S.importdatafromMarch

8

Second,sectoraltariffsonsteelandaluminumhavebeenextendedtoderivativeproductsfortheirsteeloraluminumcontent.TheWTO-IMFtrackerdataappliesaggregatedsectoralinput-outputcoefficientstoapproximatethesteelandaluminumcontentsofdownstreamproducts.

8

Bothadjustmentsshouldnarrowanydifferencebetweenthestatutoryandeffectivetariffs.

ThedailystatutorytariffsfromtheWTO-IMFtrackerarethenaggregatedatthemonthlyfre-quencybytakingthemostrecurrent(i.e.,modal)tariffrateforeachmonth.Baselinestatutorytariffsfor2024areassignedtoallmonthsbeforeFebruary2025,whenthefirsttariffchangesintheU.S.administrationwereimplemented.

Intheregressionanalysis,theeffectivetariffrateisourpreferredtariffmeasure,asitcapturesactualtariffbarriersfacedbyimportersandexporters.Toaddresspotentialendogeneity,wein-strumenttheeffectivetariffratewiththestatutoryone,whosemainadvantageisitsexogeneitywithrespecttotraderesponses—seealso

FajgelbaumandKhandelwal

(

2026

).

2.2Stylizedfacts

Figure

1

illustratestheevolutionoftheimport-weightedU.S.averagestatutory(inred)andeffec-tive(inblue)tariffratessinceJanuary2025.Thedottedlinesusefixedweightsfromthe2024im-portdata,whilethesolidlinesarebasedontime-varying(i.e.,contemporaneous)importweights.Forbothstatutoryandeffectiverates,thesolidlinesliebelowthedottedlines,reflectingthereal-locationofimportsinresponsetotariffs—fromhigher-tarifftolower-tariffgoodsandcountries.Underbothweightingschemes,thebluelinesliebelowtheredlines,indicatingthesignificantroleofexemptions,implementationcomplexitiesandlagsintheactualcollectionofstatutoryduties(

GopinathandNeiman

,

2026

).

AsofDecember2025,theaveragestatutoryrateusingtime-varyingimportweightswasaround15.5percent,approximately6percentagepointshigherthantheaverageeffectiverate.Impor-tantly,thedifferencewasnegligibleinJanuary2025butwidenedastheU.S.implementedtariffactions.Alsoacrosscountries,averageeffectivetariffsarebelowthestatutoryones,withthegapbeingparticularlylarge(around10percentagepoints)inthecaseofChina(seeFigure

A.1.1

).

toJune2025.

8TocapturetariffsimposedonChinasince2018and2019,thebaselinestatutoryU.S.tariffonimportsfromChinaiscalculatedastheeffectiverateusingtradedatafor2024.

9

Figure1:Import-weightedaverageU.S.statutoryandeffectivetariffrates

ThesubstantialvariationinUStariffpolicyacrosstradingpartnersemergesalsowithinproducts.Figure

2

showsthedistributionofthestandarddeviationofchangesinU.S.statutorytariffswithinHS8-digitproduct(thelevelatwhichstatutorytariffsareset)in2025(relativeto2024)and2019(relativeto2017).Toeasecomparisonacrosstariffepisodes,thewithin-productstandarddevi-ationsarenormalizedbytheoverallstandarddeviation—whichishigherin2025becausetariffincreasesaremoreimportantinthatepisodethanin2018-19.Twomainfindingsemerge.First,thereissignificantwithin-productvariationinthelatesttariffepisode,eveniftariffhikestargetmostcountriesandproducts.The2024-25tariffchangesdifferacrosscountriesinallproducts,withamedianvalueforthewithin-productstandarddeviationofaround8percentagepoints(57percentoftheoverallstandarddeviation).Second,tariffchangesvarymorewithinproductsinthe2018-19tariffepisode,wheretariffstargetmainlyimportsfromChina.Aspanel(b)shows,themedianofnormalizedwithin-productstandarddeviationoftariffchangesishigherinthe2018-19episodethaninthe2025one.

9

Intheempiricalanalysis,weinvestigatewhetherthisvariationintariffhikesacrosssourcecountriesleadstoreallocationofimportflows.

9Thewithin-productvariationaccountsfor26percentofoverallvariationintariffsduringthe2025episode,whileforthe2018-19episodemostofthevariation(around98percent)intariffsiswithinproducts.Thesesharesareobtainedfromcomputing1-R2fromregressionsofmonthlychangesinlogsof1+tariffsduring2025and2018-19relativetothebaselineperiods(2024for2025and2017for2018-19)onproduct-timefixedeffects—whereproductsaredefinedby8-digitcodes.

10

Figure2:Distributionofwithin-productstandarddeviationofchan