【彼得森经济研究所】低技能移民限制对美国企业和工人的影响：来自随机抽签的证据-2026.6

WORKINGPAPER

26-11TheEffectofLow-Skill

ImmigrationRestrictionsonUS

FirmsandWorkers:EvidencefromaRandomizedLottery

MichaelA.Clemens

andEthanG.Lewis

July2026

©AmericanEconomicAssociation.ThispaperhasbeenpublishedinAmericanEconomicJournal:AppliedEconomics.Reprintedwithpermission.

ABSTRACT

USfirmshiringforeignworkersinlow-skillnonfarmjobsface

MichaelA.Clemens

abindingquotaontheH-2Bvisa,allocatedinpartthrougharandomizedlottery.Weevaluatethequota’smarginalimpact

isaneconomist

andprofessorattheJohnsHopkins

usingthelottery,anovelfirmsurvey,andapreanalysisplan.Firms

UniversitySchool

exogenouslyemployingmoreH-2Bworkersinlow-skilljobsincreaseproduction(elasticity0.20–0.22),investment(1.5–2.1),andprofits

ofGovernment

andPolicyand

nonresidentsenior

(0.15).TheelasticityofsubstitutionbetweenH-2BandUSworkers

fellowatthe

isverylow(0.8–2.0).ThustheeffectonUSemploymentiszeroorpositiveoverall,andpositiveinruralareas.Forensicanalysis

PetersonInstituteforInternationalEconomics.

suggestssimilarlylowsubstitutabilityofblack-marketlabor.

EthanG.Lewisisprofessorof

JELcodes:F22,J61,D22

economicsat

Keywords:low-skillimmigration,USfirms,randomizedlottery,H-2Bvisa,USemployment,low-skilljobs,elasticityofsubstitution

DartmouthCollege.

1750MassachusettsAvenue,NW|Washington,DC20036-1903USA+

1.202.328.9000|

WP26-11|JULY20262

Note:FirmsurveyapprovedbytheDartmouthCollegeCommitteefortheProtectionofHumanSubjects#STUDY00032360.Pre-analysisplanirreversiblyregisteredbeforedatacollection,at

https://osf.io/zdyun

;

AEARCTRegistry:

/trials/16896

,

dataandcodeavailableatClemensandLewis(2025).Webenefited

frominteractionswithSureshNaidu,ThomasChaney,MelanieMorten,

RanAbramitzky,OlivierBlanchard,JeffKling,DeanYang,LeahBoustan,

ChrisWalters,JoanLlull,WilliamCollins,PaoloFalco,ChadSparber,

JeremyWeinstein,ToddSchoellman,NicolasMorales,AnnaMariaMayda,

JoanMonras,GiovanniPeri,MulySan,ParagMahajan,SharatGanapati,

Quy-ToanDo,MartaPrato,BrittaGlennon,JonathanDingel,NelsLind,

StefanoCarattini,FedericoMandelman,HyunjuLee,JustinSandefur,

GregAuclair,andseminarparticipantsattheNBERSummerInstitute,the

NBERConferenceonImmigrantsintheUSEconomy,StanfordUniversity

DepartmentofEconomics,theCESifoVeniceSummerInstitute,the

VanderbiltUniversityDepartmentofEconomics,UniversityofDelaware

DepartmentofEconomics,theFederalReserveBankofRichmond,the

BankofCanadaWorkshoponMacroeconomicImplicationsofMigration,

theFederalReserveBankofAtlanta,theCongressionalBudgetOffice,

GeorgeMasonUniversity,thePetersonInstituteforInternationalEconomics,andtheUniversityofPittsburgh.USCitizenshipandImmigrationServices

andtheUSDepartmentofLaborprovidedpublicdataonthecertificationlottery.ThefirmsurveywasdistributedbytheNationalAssociationof

LandscapeProfessionals,theOutdoorAmusementBusinessAssociation,theSeasonalEmploymentAlliance,andtheAmericanSeafoodJobs

Alliance.WeacknowledgesupportfromOpenPhilanthropyandwethankRevaResstackforresearchassistance.Anyviewsexpressedhereinare

thoseoftheauthorsaloneanddonotrepresentanyorganization.

1

1Introduction

TheefectofimmigrationonU.S.workersremainscontroversial.Ithingescruciallyonthede-greetowhichforeignworkerscomplementorsubstituteforU.S.workersinproduction.Theliteraturegenerallyfindsthatimmigrationforhigh-skillwork—requiringhighereducationandspecializedknowledge—broadlycomplementsnativelabor.Thereislessconsensusaboutimmi-grationforlow-skillwork(

Dustmannetal.2016a

;

Blauetal.2017

,267;

BlauandHunt2019

,174;

Edoetal.2020

).Despitethegreateconomicandpoliticalimportanceofrestrictionsonlow-skillimmigration,estimatesofitsefectrangewidelydependingontheassumptionsusedtoapprox-imatecausalidentification(

Card1990

;

Borjas2003

;

OttavianoandPeri2012

;

Dustmannetal.

2016b

).

Herewestudytheeconomicefectsoflow-skillimmigrationusinganovel,large-scalepolicyexperimentintheUnitedStates:nationwide,firm-level,naturalrandomizationofrestrictionsontheemploymentofimmigrantsinlow-skilljobs.TheUnitedStateshasoneprincipalworkvisaforlow-skilllaborinthenonfarmeconomy—theH-2Bvisa.U.S.employers’accesstothatvisaislimitedbyaquotaandallocatedinpartviaarandomizedlotteryconductedbythefederalgovernment.Thisexogenousvariationallowsunusuallytransparent,policy-relevantestimatesofhowlow-skillimmigrationrestrictionsafectU.S.firmsintheshortrun.

Wefirstpre-registeredthehypothesistests,predictedtreatmentefects,andsubgrouphetero-geneitytestsimpliedbyasimplemodelofamonopolistically-competitivefirmfacingapoten-tiallyimperfectly-competitiveinputmarketforforeignandU.S.workers.Wethencollectedsurveydataon472firmscomprisingbothwinnersandlosersoftheH-2Bvisalotteriesformid-2021andmid-2022.Thisallowspre-specifiedtestsofbasictheoreticalpredictionsaboutthemagnitudeandheterogeneityoftheefectoflow-skillimmigrationrestrictions.Itfurthermoreallowspolicy-relevantestimatesofthefirm-level“combined”elasticityofsubstitution(

Hicks

1936

)betweenH-2BandU.S.workers.

1

WefindthatexogenousincreasesinH-2Bworkeremploymentforlow-skillworkcausethe

1Wefollowtheindustry-standarddefinitionof“U.S.workers”tocompriseU.S.citizensorlawfulpermanentresi-dents(green-cardholders).

2

marginalfirmtoexpandoperations.Putdiferently,restrictionsonH-2Bemploymentcausethemarginalfirmtocontract.Losingthelotteryreducesfirms’employmentoflow-skillimmigrantsbyabouthalf(–0.62logpoints).Atthemarginalfirm,thiscausesreducedrevenuewithelasticity0.20–0.22,reducedinvestmentwithelasticity1.5–2.1,andareducedrateofprofitwithelasticity0.15(allstatisticallypreciseatconventionallevels).Acrossallfirmscollectivelythisrestrictioneitherdoesnotafectorcausesareductioninemploymentoflow-skillU.S.workers,withelas-ticity0.06–0.19(statisticallyimpreciseinsomespecifications).Inpre-registeredsubsamplesoffirmslocatedinruralareas,thisreducedemploymentoflow-skillH-2Bworkerscausesreducedemploymentoflow-skillU.S.workers,withelasticity0.61(statisticallyprecise).Weestimatethatthefirm-level,policy-relevantefectiveelasticityofsubstitutionbetweenforeignH-2BlaborandU.S.laborinlow-skillworkisverylow,intherange0.8–2.0.

Overall,thisevidenceisconsistentwithsubstantialnegativeefectsoflow-skillimmigrationre-strictionsoneconomicactivityinsideandoutsiderestrictedfirms—especiallysmallfirmsandthoseinruralareas.Theseefectsarerobusttoseveralprespecifiedchanges,includingalter-nativedefinitionsoftheinstrumentalvariable,controlforthefamilywiseerrorrate,andtestsforglobalanditemnonresponse.Theyarelikewiserobusttoseveralchangesthatwerenotpre-specified,includingsensitivitytoinfluentialobservations,randomizationinference,andforensictestsforunobservedblack-marketemployment.

Wecontributetotheliteratureinthreedimensions.First,wearenotawareofpriorworklever-agingpolicy-relevantrandomizationtotransparentlyidentifytheefectsofrestrictionsonfirms’demandforlow-skillimmigrantlabor.

2

Thestandardapproachintheliteratureistoconstruct‘shift-share’instrumentalvariablesassumingthatpersistenceinimmigrantpresenceactstoex-ogenouslyallocatemorerecentimmigrationacrossregionsorfirms.

3

Butunobservedfactors

2Otherstudieshaveusednaturally-randomizedrefugeeplacementtostudyexogenousvariationinsupply,butnotvariationinrestrictionsondemand(

Glitz2012

;

Couttenieretal.2019

;

OlneyandPozzoli2021

).Somehaveexploitedrandomizedvisaallocationacrossindividualstostudytheefectsofmigrationonmigrantsandtheirfamilies(

Gibsonetal.2011

;

Mergo2016

;

Mobaraketal.2020

;

Buecheletal.2021

).Thehandfulofstudiesexploitingnaturallyrandomizedrestrictionsonfirms’demandforimmigrantlaborfocusexclusivelyonhigh-skillworkers(

Clemens2013

;

Doranetal.2022

;

Dimmocketal.2022

;

Brinattietal.2023

).AlimitationofthatworkisthatintheUnitedStates,naturalrandomizationofhigh-skillworkvisapetitionsoccursattheleveloftheindividualforeignworker,notatthelevelofthefirm.Thiscanonlyproducesubstantialrandomvariationintheimmigrantshareofemploymentacrosssmallfirmswithfewpetitions;themorepetitionsafirmfiles,themorelikelyitistoreceiveauniform,fixedshareofthoseworkers(

Perietal.2015

).Inthelow-skillvisawestudy,randomizationoccursnotattheindividuallevelbutatthefirmlevel(withnuancesdiscussedbelow).

3Usingregions:

Card

(

1990

);

AltonjiandCard

(

1991

);

Burchardietal.

(

2018

);

Monras

(

2020

);

Piyapromdee

(

2020

);

3

thatshapeeconomicoutcomescanalsopersist,withpotentialforbiasedestimation(

Jaegeretal.

2018

;

Adãoetal.2019

;

Goldsmith-Pinkhametal.2020

;

Borusyaketal.

2021

).Ouruseofnaturalrandomizationfurthermoreaddressestheliteratureonhowfirmsrespondtoshocksmoregen-erally(

BaqaeeandFarhi2019

;

BilbiieandMelitz2021

;

Buttersetal.2022

;

Guerrierietal.2022

;

Kumaretal.2022

).

Second,weexploreefectsatthefirmlevel.Within-firmresponsesarecentraltotheoveralleconomicefectofimmigration(

CardandLewis2007

;

LewisandPeri2015

;

Dustmannetal.

2015

;

Peri2016

).Recentstudyoffirm-levelefectsfocusesonhigh-skillimmigration,especiallyitsefectsoninnovationandentrepreneurship.

4

Thisworkconsidersimmigrationforlow-skillwork,complementingongoingresearchby

Amuedo-Dorantesetal.

(

2024

).

5

Anadvantageoffirm-levelresearchisthatitdoesnotrequirethestrongassumptionofrulingoutspecializationacrossfirmswithintheaggregates—suchasskill-cellsorgeographicareas—thataretypicallytheunitofanalysis(

Card2009

,2).

6

Third,wecontributeestimatesbasedonexogenouschangesinpolicy.TheLocalAverageTreat-mentEfect(LATE)estimatedfromstandard‘shift-share’instrumentalvariables,evenwhenin-ternallyvalid,maybesubstantiallybiasedasanestimateofthePolicy-RelevantTreatmentEfect(PRTE;

HeckmanandVytlacil2001

;

HeckmanandVytlacil2005

;

Carneiroetal.2011

).Intuitively,the‘supplypush’LATEofvaryingthesupplyofimmigrantsregardlessofcurrentdemandfortheirlabor—asthe‘shift-share’approachisdesignedtodo—neednotequaltheLATEfrompolicy-inducedrestrictionsoncurrent,realizeddemandfortheirlabor.Arelativelysmallandrecent

literaturefocusesinsteadonexogenouschangesinpolicyrestrictions.

7

Kimetal.

(

2022

).Usingfirms:

Lewis

(

2011

);

Olney

(

2013

);

DustmannandGlitz

(

2015

);

Mitaritonnaetal.

(

2017

);

Bursteinetal.

(

2020

);

Grayetal.

(

2020

);

Imbertetal.

(

2022

);

Mahajan

(

2024

).

4

KerrandLincoln

(

2010

);

HuntandGauthier-Loiselle

(

2010

);

Hunt

(

2011

);

Hornung

(

2014

);

Kerretal.

(

2015

);

Maydaetal.

(

2018

);

Boundetal.

(

2017

);

Maydaetal.

(

2023

);

Baharetal.

(

2020

);

KhannaandLee

(

2019

);

Glennon

(

2020

);

Glennonetal.

(

2021

);

Raux

(

2021

);

Azoulayetal.

(

2022

).

5

Amuedo-Dorantesetal.

likewisestudytheefectsofH-2Bvisaaccessonfirms,usingadministrativedataontheuniverseofH-2Bvisasponsoringfirmsin2018,butwithafundamentallydiferentidentificationstrategythatleveragesasuddenchangeintheavailabilityofvisas.Wecomparethetwostudies’resultsbelow.

6Resultsfrommoreaggregateapproachescanbesensitivetothedefinitionoftheaggregates,embodyingas-sumptionsaboutwithin-andcross-cellsubstitution(

Boustan2009

;

Dustmannetal.2016a

,33).Firm-levelstudiescanalsoclarifythemechanismofadjustmenttoimmigration,suchastherelativeimportanceofshiftsinproductiontechniqueswithinfirmsandshiftsinthesizedistributionoffirms(

DustmannandGlitz2015

;

FogedandPeri2016

).

7Onhigh-skillimmigrants:

Beerlietal.

(

2021

);onlow-skillimmigrants:

Dustmannetal.

(

2016b

);

Clemensetal.

(

2018

);

Ayromlooetal.

(

2020

);

IftandJodlowski

(

2022

);

LuoandKostandini

(

2022

);

San

(

2023

);

Eastetal.

(

2023

);

Abramitzkyetal.

(

2023

).

4

2TheUnitedStates’low-skill,nonfarmworkvisaprogram

Westudynatural,firm-levelrandomizationofaccesstotheprincipalworkvisaforlow-skilllaborintheU.S.nonfarmeconomy,the‘H-2B’visa.Itistheonlyemployment-basedvisaavailabletoforeignworkerswithoutacollegeeducationworkingoutsideagriculture,withimmaterialexceptions.98%ofallH-2Bjobsdonotrequireahighschooleducation;themeanmonthsofexperiencerequiredbyemployersis1.2.

8HaalandandRoth

(

2020

)usepoliticalsupportforexpandingtheH-2Bvisaasaproxymeasureofsupportforlow-skillimmigrationingeneral.Thisvisahasundergonerelativelylittlestudydespiteitsimportance.U.S.county-yearswhereemployerspetitionformoreH-2BworkersdonotexhibithigherunemploymentorlowerwagesonaverageforU.S.workersinrelatedlow-skillserviceoccupations(

Amuedo-Dorantesetal.

2021

),butfurtherinvestigationofthatobservedcorrelationiswarranted.

ThelegaloriginofthevisaistheImmigrationandNationalityActof1952.Itcreatedalow-skillnonimmigrantworkvisaforbothfarmandnonfarmwork—named‘H-2’aftertheAct’srelevantparagraph(66Stat168§101(a)(15)(H)(ii)).Aseparate‘H-2B’visafornonfarmlow-skillworkwascreatedbytheImmigrationReformandControlActof1986(

Pickral2007

).AnH-2Bworkerisdefinedbylawas“havingaresidenceinaforeigncountrywhichhehasnointentionofabandoningwhoiscomingtemporarilytotheUnitedStatestoperform...temporary[non-agricultural]serviceorlaborifunemployedpersonscapableofperformingsuchserviceorlaborcannotbefoundinthiscountry.”WagesforH-2Bworkersarefixedbythefederalgovernmentattheprevailingwage,“themeanwagefortheoccupationinthepertinentgeographicareaderivedfromtheBureauofLaborStatisticsOccupationalEmploymentStatisticssurvey”.

9

Foreignworkersreceivedanaverageof84,383H-2Bvisasperyearduringthefivefiscalyearsendingin2021.88%aremale.

10

TheleadingindustriesemployingH-2BworkersareAdmin-istrativeandSupportServices(especiallygroundskeeping/landscaping);Hospitality(includingrestaurants);Arts,Entertainment,andRecreation;Forestry,FishingandHunting;Construction;

8Dept.ofLaborclassificationofcertifiedpositionsinFY2021disclosuredata.

9“WageMethodologyfortheTemporaryNon-AgriculturalEmploymentH-2BProgram”,FederalRegister

80FR

24145

.

10Infiscal2021,thelatestdatareleasedatthetimeofwriting,DHSreports123,046entries(I-94only)onH-2Bvisas,ofwhich15,374women:DHS,“

NonimmigrantAdmissionsbySelectedClassesofAdmissionandSexandAge

”.

5

Figure1:WoRksITEsoFH-2BvIsApETITIoNsByU.S.couNTy,2021–2022(uNIvERsE)

Fulluniverseofcap-subjectpetitionscertifiedbytheDept.ofLabor,fiscalyears2021and2022(

DOL2022

).Countyofworksite,notnecessarilyofthepetitioningfirm.Therewerecertifiedpetitionsfromall50statesplustheDistrictofColumbiaandPuertoRico.Boundarycoordinatesfrom

USCensusBureau

(

2016

).

andFood,Beverage,Textile,andApparelManufacturing(

Barnes2020

,12).Theseroughlycor-respondtothelow-skillserviceindustrieswiththehighestprevalenceofimmigrantworkersintheUnitedStates,ledbylandscaping(

Cortés2008

,387).ThelargemajorityofworkersarecitizensofMexico(75%inFY2021);mostoftherestarecitizensofJamaica,Guatemala,Ukraine,Honduras,Serbia,thePhilippines,andElSalvador.

EmployerscaninprincipleemployanygivenH-2Bworkerindefinitelyprovidedthattheyapplysuccessfullytoextendthevisaonceayear,andthattheworkerappliestorenewthevisaonceeverythreeyearsbydepartingtheUnitedStatesforthreemonths.ButinpracticetheDepart-mentofLaborisunlikelytoapprovelong-termrehiringassatisfyingatemporaryneed.H-2Bjobsmustoferfull-timeemployment,definedasatleast35hoursperweekandatleast75%oftheworkdaysineach12-weekperiod.Workers’spousesandminorchildrencanaccompanythemintothecountry,butmaynotwork(anddonotcountagainstthevisacap).Themigrants’worksitesarewidelydistributedacrossthecountry,inall50statesplustheDistrictofColumbia,andspanningbothruralandurbanareas(

Figure1

).

6

TohireanH-2Bworker,employersmustsuccessfullypetitiontwofederalgovernmentagencies,inorder:theDepartmentofLabor(DOL),andtheDepartmentofHomelandSecurity(DHS).DOLmustcertifythattheH-2Bjobcomplieswithlaborlaw;DHSmustauthorizeissuanceofaworkvisa.Foreachemployer’spetition,DOLcertifiesthathiringtheforeignworkerwillnotadverselyafectthewagesoremploymentofU.S.workers,andthatthehiringneedis‘intermittent’,‘peakload’,‘one-timeoccurrence’,or‘seasonal’.

11

Ontheaveragepetition,88.1%ofrequestedworkerswerecertifiedinfiscalyear2021and78.8%infiscalyear2022.ForDOL-certifiedworkers,em-ployersmustthenpetitionDHS,whichdecideswhethertherearesufficientvisasforthepetitionandwhetheranythingdisqualifieseachworkerfromreceivingavisa.Afirmhiringagroupofworkerstoprovidethesameserviceatthesamelocationcanlistupto25workersonthesame

12

petition.

Thisregulatoryprocesswascreatedtoaddresslawmakers’enduringsuspicionsofnegativelabor-marketefectsfromlow-skillworkvisas.Between1885and1952,thecontracthiringoflow-skillforeignworkerswasbannedoutrightbytheForanAct,

13

becausehiringofthistypewasconsideredharmfultotheemploymentprospectsoflow-skillU.S.workers(

Orth1907

).Thesame1952lawthatreversedthisban,creatingtheH-2visa,requiredDOLtocertifythattherewereinsufficientU.S.workers“able,willing,andqualified”toperformeachindividualjobforwhichaforeignworkerwastobecontracted(

Wasem2003

).

Theefficacyofthatcertificationprocesshasbeenfrequentlyquestionedsincethen,notablybytheinfluential

Hesburgh

(

1981

,226)Commission.Itsrecommendationsculminatedinthe1990lawtightlyrestrictingallvisasbasedonlow-skill,nonfarmemployment—cappingtheH-2Bvisa(

Schuck1992

,53;

ChishtiandYale-Loehr2016

)aswellasallbuteliminatingemployment-basedgreencardsforlow-skillwork(

Aragones1991

,125;

AdlerandJarrett1992

,791).Whetherornotthoserestrictionsachievedtheirexplicitobjective—toraiseemploymentforU.S.workersrelative

tothecounterfactual—doesnotappeartohaveundergonesystematicempiricaltests.

11Thisroughlyfour-monthadministrativeprocessisdetailedby

Bruno

(

2018

),

Barnes

(

2020

)and

Bier

(

2021

).12

8CFR214.2(h)(2)(ii)

.

13

23Stat.332

,48thCongress,Sess.II,Chap.164.

7

3Firm-levelrandomizationoflow-skillimmigrantemployment

TwofeaturesoftheinstitutionalprocessforH-2Bvisaallocationcreatethenaturalexperimentthatwestudy.

First,theH-2Bvisaissubjecttoastatutorycapof66,000peryear.ThiscapwaswrittenintolawbytheImmigrationActof1990,andremainsinforce(8USC§1184(g)(1)(B)).In2005itwassplitintoalimitof33,000visasforthefirsthalfofeachfiscalyear(October–March)and33,000forthesecondhalf(April–September)(

Bruno2018

).ThecapwassetwithoutanyquantitativeempiricalevidenceofitsefectsontheU.S.labormarket.By2022thestatutorycapwasoversubscribedbyseveralhundredpercent:Forthe33,000visasinthestatutoryquotaforthesecondhalfofFY2022,employerspetitionedDOLfor136,555workers.

14

Second,anaturallyrandomizedlotteryconstrainsfirms’accesstoH-2Bvisasunderthestatu-torycap.BecauseDOLcertificationisrequiredbeforefirmscanpetitionDHSforavisa,andbecausethedemandforvisasatDHSgreatlyexceedsthesupply,firms’abilitytoobtainavisaatDHSishighlydependentonhowquicklytheycancompleteprocessingatDOL.Knowingthis,andtoensureequitableaccesstovisasacrossfirms,DOLbeginsprocessingfirms’petitionsinrandomizedorder.Itbegandoingthisafteranunprecedentednumberofpetitionswerereceivedforthesecondhalfoffiscalyear2019,causingtheDOLservertocrashandmakingitimpossibletodeterminetheorderinwhichpetitionshadbeenfiled.

15

DOLrandomlyassignseachpetitionaletter:AthroughEin2021,AthroughGin2022.ItbeginsprocessingtheApetitionsfirst,andstartstheBpetitionswhenstafbecomeavailablebuttherearenonewApetitionslefttobegin(butotherstafmaystillbefinishingsomeApetitions).ItthenproceedstopetitionswithletterC,D,Eandsoforthinorder(

Figure2

).PetitionsreceivinganAresultarehighlylikelytoemergefromDOLprocessingbeforethevisacapisreached;petitionswithallotherresultsarenot.TheresultisthatthereisalargerandomcomponenttotheorderinwhichfirmsgetpasttherequiredDOLadministrativestep,andthustheirabilitytopetitionDHSforvisasbeforethestatutoryquotaofvisasisexhausted.

14FederalRegisterMay18,2022,

87FR30334

.Notethatthevisaquotaverytightlybindsnotjustdemandbutsupply:ThereislittleconstraintonlaborsupplygiventhatH-2Bjobscommonlyofermigrantworkersover1,000%oftheirhome-countryreservationwage(

Brodbecketal.2018

).

15FederalRegister,March4,2019,

84FR7403

.

8

Figure2:H-2BFoREIGNwoRkERpETITIoNDEcIsIoNDATEsByLoTTERyREsuLT,uNIvERsEoFFIRms

(a)Fiscalyear2021,secondhalf

Petitionsperday

Lo性eryAGuaranteedvisaSupplemental

endsquotaexhaustedvisasannounced

B

C

D

E

Jan.1Feb.1Mar.1Apr.1May1Jun.1

Decisiondate,2021

125

100

75

50

25

0

(b)Fiscalyear2022,secondhalf

Petitionsperday

E

DF

C

G

Jan.1Feb.1Mar.1Apr.1May1Jun.1

Decisiondate,2022

Lo性eryends

A

B

125

100

75

50

25

0

Guaranteedvisaquotaexhausted

Supplemental

visasannounced

Theunitofobservationispetitions.ShownistheuniverseoffirmsenteringtheJanuarylotteryforworktobeperformedinthesecondhalfofeachfiscalyear(April1–September30).Epanechnikovkerneldensities,bandwidth2days.‘Decisiondate’isthedateoftheDepartmentofLabor’sdecisiononwhetherornottocertifyeachpetition,anecessaryconditionofproceedingtopetitionUSCISforavisa.

9

Inthisnaturalexperiment,weconsider‘treatment’aseachU.S.firm’semploymentoflow-skillimmigrantworkersonH-2Bvisas.Randomizationintotreatmentatthefirmleveliscontinuousandfuzzy.

Treatmentiscontinuousbecauserandomizationisatthepetitionlevel,notnecessarilythefirmlevel.Formostfirms,thisdoesequatetorandomizationatthefirmlevel,becausethelargema-jorityoffirmsfileasinglepetitionforagroupofworkers(median11workersperpetition).Butgroupsofworkersperformingdiferentoccupationsatdiferentworksitescanberequestedonmultipleseparatepetitionsbythesamefirm.Sincelargerfirmsaremorelikelytofilemultiplepe-titions,wemeasuretreatmentbythefractionofworkerspetitionedforbyeachfirm—acrossoneormultiplepetitions—thatreceivetimelyDOLcertification.Thatfractionisrandomlyassignedatthefirmlevel.RandomizationoccursacrosstheuniverseofH-2Bemployersnationwide,ob-viatingsiteselectionbias(

Allcott2015

).

TreatmentisfuzzybecausetherearewaysforsomefirmstohireH-2BworkersregardlessoftheirDOLlotteryresult—thatis,therearesome‘always-taker’firms(

Angristetal.

1996

).First,theworkersonapetitionareexemptfromthevisacapiftheyarealreadypresentintheUnitedStates(12.7%ofworkersinthelottery).ForthemtherandomizedtimingofDOLprocessingdoesnotafecttheiraccesstovisas.Second,firmsthatare“cappedout”—thatis,firmsthatreceiveDOLcertificationafterthe33,000visaquotaforthatsemesterisexhausted—cansometimesobtainanH-2Bvisafroma“supplemental”visaallocationcreatedinthemiddleoftherelevantsemester.Bythetimesuchsupplementalallocationsareannounced,almostallfirmshavecompletedDOLprocessing,sotheiraccesstoanysupplementalvisasisnotlegallyrestrictedbytheDOLlottery.Butthelotteryresultneverthelessstronglyinfluencesfirms’H-2Bhiring.Thisisbecause1)itisexanteuncertainwhetherasupplementalallocationwilloccuratall,andifthereisone,2)itisexanteuncertainhowlargeanysupplementalallocationwillbe,but3)supplementalallocationsaregenerallyfarlowerthanemployerdemand.

16

16DHShasdiscretionunderlawtoapprovesupplementalH-2Bvisas.Itinterpretsthislegalauthoritytoallowissuanceofamaximumof64,716supplementalvisasperyear,toreflect“theneedsofAmericanbusiness”(FederalRegister,May25,2021,

86FR28205

).Butinpractice,thenumberofsupplementalvisasapprovedisfarlessthanthemaximumallowedandfarlessthanthenumberrequestedbyemployers—ifanysuppleme