美国联邦税制概览

OVERVIEWOFTHEFEDERALTAXSYSTEMASINEFFECTFOR2007PreparedbytheStaffoftheJOINTCOMMITTEEONTAXATIONJanuary12,2007JCX-2-07iCONTENTSPageINTRODUCTION..........................................................................................................................1I.SUMMARYOFPRESENT-LAWFEDERALTAXSYSTEM...........................................2A.IndividualIncomeTax.....................................................................................................2B.CorporateIncomeTax.....................................................................................................8C.EstateandGiftandGeneration-SkippingTransferTaxes.............................................12D.EmploymentTaxes........................................................................................................14E.MajorExciseTaxes........................................................................................................15II.HISTORICALRECEIPTSDATA......................................................................................161INTRODUCTIONThisdocument,1preparedbythestaffoftheJointCommitteeonTaxation,providesasummaryofthepresent-lawFederaltaxsystemasineffectfor2007.ThecurrentFederaltaxsystemhasfourmainelements:(1)anincometaxonindividualsandcorporations(whichconsistsofbotha“regular”incometaxandanalternativeminimumtax);(2)payrolltaxesonwages(andcorrespondingtaxesonself-employmentincome);(3)estate,gift,andgenerationskippingtaxes,and(4)excisetaxesonselectedgoodsandservices.Thisdocumentprovidesabroadoverviewofeachoftheseelements.2AnumberofaspectsoftheFederaltaxlawsaresubjecttochangeovertime.Forexample,somedollaramountsandincomethresholdsareindexedforinflation.Thestandarddeduction,taxratebrackets,andtheannualgifttaxexclusionareexamplesofamountsthatareindexedforinflation.Ingeneral,theInternalRevenueServiceadjuststhesenumbersannuallyandpublishestheinflationadjustedamountsineffectforataxyearpriortothebeginningofthatyear.Whereapplicable,thisdocumentgenerallyincludesdollaramountsineffectfor2007andnoteswhetherdollaramountsareindexedforinflation.Inaddition,anumberoftheprovisionsintheFederaltaxlawshavebeenenactedonatemporarybasisorhaveparametersthatvarybystatutefromyeartoyear.Forexample,therecentlyenactedTaxReliefandHealthCareActof2006extendedanumberofexpiredorsoontoexpireprovisionsonatemporarybasis.Inaddition,theprovisionsoftheEconomicGrowthandTaxReliefReconciliationActof2001wereinitiallygenerallytoexpireattheendof2010;someprovisionsofthatActhavesubsequentlybeenmodifiedormadepermanent.Forsimplicity,thisdocumentdescribestheFederaltaxlawsineffectin2007andgenerallydoesnotincludereferencestoprovisionsastheymaybeineffectforfutureyearsortoterminationdatesforexpiringprovisions.AlistofexpiringtaxprovisionsmaybefoundinJointCommitteeonTaxation,ListofExpiringFederalTaxProvisions2006-2020,(JCX-1-07),January11,2007.1Thisdocumentmaybecitedasfollows:JointCommitteeonTaxation,OverviewoftheFederalTaxSystemasinEffectfor2007(JCX-2-07),January12,2007.2Ifcertainrequirementsaremet,certainentitiesororganizationsareexemptfromFederalincometax.Adescriptionofsuchorganizationsisbeyondthescopeofthisdocument.2I.SUMMARYOFPRESENT-LAWFEDERALTAXSYSTEMA.IndividualIncomeTaxIngeneralAUnitedStatescitizenorresidentaliengenerallyissubjecttotheU.S.individualincometaxonhisorherworldwidetaxableincome.3Taxableincomeequalsthetaxpayer'stotalgrossincomelesscertainexclusions,exemptions,anddeductions.Graduatedtaxratesarethenappliedtoataxpayer’staxableincometodeterminehisorherindividualincometaxliability.Ataxpayermayfaceadditionalliabilityifthealternativeminimumtaxapplies.Ataxpayermayreducehisorherincometaxliabilitybyanyapplicabletaxcredits.AdjustedgrossincomeUndertheInternalRevenueCodeof1986(the“Code”),grossincomemeans“incomefromwhateversourcederived”exceptforcertainitemsspecificallyexemptorexcludedbystatute.Sourcesofincomeincludecompensationforservices,interest,dividends,capitalgains,rents,royalties,alimonyandseparatemaintenancepayments,annuities,incomefromlifeinsuranceandendowmentcontracts(otherthancertaindeathbenefits),pensions,grossprofitsfromatradeorbusiness,incomeinrespectofadecedent,andincomefromScorporations,partnerships,4trustsorestates.5Statutoryexclusionsfromgrossincomeincludedeathbenefitspayableunderalifeinsurancecontract,interestoncertainStateandlocalbonds,employer-providedhealthinsurance,employer-providedpensioncontributions,andcertainotheremployer-providedbenefits.Anindividual’sadjustedgrossincome(“AGI”)isdeterminedbysubtractingcertain“above-the-line”deductionsfromgrossincome.Thesedeductionsincludetradeorbusinessexpenses,capitallosses,contributionstoatax-qualifiedretirementplanbyaself-employedindividual,contributionstoindividualretirementarrangements(“IRAs”),certainmovingexpenses,andalimonypayments.3ForeigntaxcreditsgenerallyareavailableagainstU.S.incometaximposedonforeignsourceincometotheextentofforeignincometaxespaidonthatincome.AnonresidentaliengenerallyissubjecttotheU.S.individualincometaxonlyonincomewithasufficientnexustotheUnitedStates.4Ingener