亨格瑞成本与管理会计（第16版） 课件Chapter 21Inventory Management,Just-in-Time,and Simplified Costing Methods

CostAccountingSeventeenthEdition,GlobalEditionChapter21InventoryManagement,Just-in-Time,andSimplifiedCostingMethodsCopyright©2021PearsonEducationLtd.LearningObjectives(1of2)21.1Identifysixcategoriesofcostsassociatedwithgoodsforsale21.2

Balanceorderingcostswithcarryingcostsusingtheeconomic-order-quantity(EOQ)decisionmodel21.3IdentifytheeffectoferrorsthatcanarisewhenusingtheEOQdecisionmodelandwaystoreduceconflictsbetweentheEOQmodelandmodelsusedforperformanceevaluation21.4

Describewhycompaniesareusingjust-in-time(JIT)purchasingLearningObjectives(2of2)21.5Distinguishmaterialsrequirementsplanning(MRP)systemsfromjust-in-time(JIT)systemsformanufacturing21.6Identifythefeaturesandbenefitsofajust-in-timeproductionssystem21.7Describedifferentwaysbackflushcostingcansimplifytraditionalinventory-costingsystems21.8UnderstandtheprinciplesofleanaccountingInventoryManagementinRetailOrganizationsInventorymanagementincludesplanning,coordinating,andcontrollingactivitiesrelatedtotheflowofinventoryinto,through,andoutofanorganization.Anumberofdifferenttypesofcostsareassociatedwithinventoryotherthanthecostoftheactualgoodspurchased.CostsAssociatedwithGoodsforSaleOverviewManaginginventoriestoincreasenetincomerequireseffectivelymanagingcoststhatfallintothesesixcategories:PurchasingcostsOrderingcostsCarryingcostsStockoutcostsQualitycostsShrinkagecostsCostsAssociatedwithGoodsforSaleDetails(1of3)Purchasingcostsarethecostofgoodsacquiredfromsuppliers,includingincomingfreightcosts.Usuallythisisthelargestcostcategoryofgoodsininventory.Orderingcostsarethecostsofpreparingandissuingpurchaseorders,receivingandinspectingtheitemsincludedintheorders,andmatchinginvoicesreceived,purchaseorders,anddeliveryrecordstomakepayments.CostsAssociatedwithGoodsforSaleDetails(2of3)Carryingcostsarethecoststhatarisewhilegoodsarebeingheldininventory.Thesecostsincludetheopportunitycostoftheinvestmenttiedupininventoryandcostsassociatedwithstorage.Stockoutcostsarethecoststhatarisewhenacompanyrunsoutofaparticularitemforwhichthereiscustomerdemand(stockout).Thecompanymustactquicklytoreplenishinventorytomeetthatdemandorsufferthecostsofnotmeetingit.CostsAssociatedwithGoodsforSaleDetails(3of3)CostsofQualityarethecostsincurredtopreventandappraise,orthecostsarisingasaresultof,qualityissues.RecallfromChapter20thefourcategoriesofqualitycosts:PreventionAppraisalInternalfailureExternalfailureShrinkagecostsarecoststhatresultfromtheftbyoutsiders,embezzlementbyemployees,andmisclassificationsormisplacementofinventory.Shrinkageismeasuredbythedifferencebetweenthecostofinventoryrecordedonthebooksversusthecostofinventorywhenphysicallycounted.TheEconomic-Order-QuantityDecisionModelHowmuchshouldafirmorderofagivenproduct?Theeconomic-order-quantity(EOQ)isadecisionmodel,that,underagivensetofassumptions,calculatestheoptimalquantityofinventorytoorder.Let’slookatsomeofthebasicEOQassumptions.BasicEOQAssumptionsThesimplestversionoftheEOQmodelassumesthereareonlyorderingandcarryingcosts.Thesamequantityisorderedateachreorderpoint.Demand,orderingcosts,andcarryingcostsareknownwithcertainty,asisthepurchaseorderleadtime(thetimebetweenplacinganorderanditsdelivery).Purchasingcostsperunitareunaffectedbythequantityordered.(Therefore,purchasingcostsareirrelevant.)Nostockoutsoccur.Managersconsiderthecostsofqualityandshrinkagecostsonlytotheextentthatthesecostsaffectorderingorcarryingcosts.EOQFormula—ResultsintheQuantityThatMinimizesAnnualRelevantTotalCostsD=DemandinunitsforspecifiedperiodQ=Sizeofeachorder(orderquantity)P=RelevantorderingcostsperpurchaseorderC=RelevantcarryingcostsofoneunitinstockforthetimeperiodusedforDOrderingandCarryingCostsIllustratedExhibit21.1GraphicAnalysisofOrderingCostsandCarryingCostsforUX1SunglassesatGlareShadeWhentoOrder(AssumesCertaintyofDemandandLeadTime)Theseconddecisioninmanaginggoodsforsaleiswhentoorderagivenproduct.Thereorderpointisthequantitylevelofinventoryonhandthattriggersanewpurchaseorder.Thereorderpointissimplesttocomputewhenbothdemandandthepurchase-orderleadtimeareknownwithcertainty.OrderingPointsIllustratedExhibit21.2InventoryLevelofUX1SunglassesatGlareShadeSafetyStock(DemandandLeadTimeUncertain)SafetystockisinventoryheldatalltimesregardlessofthequantityofinventoryorderedusingtheEOQmodel.Safetystockisabufferagainstunexpectedincreasesindemand,uncertaintyaboutleadtime,andunavailabilityofstockfromsuppliers.Managersuseafrequencydistributionbasedonpriordailyorweeklylevelsofdemandtocomputesafety-stocklevels.Companiesaregettingincreasinglysophisticatedatunderstandingcustomersusingtechniquessuchasdesignthinkinganddataanalytics.Thisdeeperunderstandingreducestheuncertaintiesaboutdemandthatcompaniesfaceandtheneedtoholdlargequantitiesofsafetystock.EstimatingInventory-RelatedRelevantCostsandTheirEffectsTherelevantcostsarecategorizedasfollows:Carryingcosts—seenextslideformoredetailsStockoutcosts—thecostofexpeditinganorderfromasupplierOrderingcosts—thoseorderingcoststhatchangewiththenumberofordersplacedCarryingCostsRelevantinventorycarryingcostsconsistofrelevantincrementalcostsandtherelevantopportunitycostofcapital.Relevantincrementalcosts—thosecostsofthepurchasingfirmthatchangewiththequantityofinventoryheld.RelevantOpportunityCostsofCapitalRelevantopportunitycostofcapital—thereturnforgonebyinvestingcapitalininventoryratherthanelsewhereItiscalculatedastherequiredrateofreturnmultipliedbytheper-unitcostsofacquiringinventory,suchasthepurchasepriceofunits,incomingfreight,andincominginspection.Opportunitycostsarealsocomputedoninvestmentsiftheseinvestmentsareaffectedbychangesininventorylevels.CostofaPredictionErrorPredictingrelevantcostsisdifficultandseldomflawless,whichraisesthequestion,“Whatisthecostwhenactualrelevantcostsdifferfromtheestimatedrelevantcostsusedfordecisionmaking?”Determiningthecostofapredictionerrorhasthreesteps:Computethemonetaryoutcomefromthebestactionthatcouldbetaken,giventheactualamountofthecostinput(costperpurchaseorder).Computethemonetaryoutcomefromthebestactionbasedontheincorrectpredictedamountofthecostinput(costperpurchaseorder).Computethedifferencebetweensteps1and2.EOQDecisionModelandManagers’PerformanceEvaluationWhathappensiftheorderquantitybasedontheEOQdecisionmodeldiffersfromtheorderquantitymanagerswouldchoosetomaketheirownperformancelookbest?Forexample,wehavelearnedthattheEOQmodeltakesintoaccountopportunitycosts.However,managersevaluatedonfinancialaccountingnumberswillignoreopportunitycosts.Managersinterestedinmakingtheirownperformancelookbetterwillonlyfocusonmeasuresusedtoevaluatetheirperformance.ConflictsarisebetweentheEOQmodel’soptimalorderquantityandthequantitythatmanagersregardasoptimal.Just-in-TimePurchasing(1of2)Just-in-time(JIT)purchasingisthepurchaseofmaterialsorgoodssothattheyaredeliveredjustasneededforproductionorsales.JITpurchasingisnotguidedsolelybytheEOQmodelbecausethatmodelonlyemphasizesthetrade-offbetweenrelevantcarryingandorderingcosts.Just-in-TimePurchasing(2of2)JITreducesthecostofplacingapurchaseorder.Long-termpurchasingagreementsdefinepriceandqualityterms.Individualpurchaseorderscoveredbythoseagreementsrequirenoadditionalnegotiationregardingpriceorquality.Companiesareusingelectroniclinkstoplacepurchaseordersatasmallfractionoftraditionalmethods(phoneormail).Companiesareusingpurchase-ordercards(similartoconsumercreditcards).RelevantCostsinJITPurchasingRelevantcostsfortheEOQmodelarethecarryingandorderingcosts.Inventorymanagementincludespurchasingcosts,stockoutcosts,costsofquality,andshrinkagecosts.JITrelevantcostsPurchasingcostsOrderingcostsOpportunitycostsCarryingcostsStockoutcostsQualitycostsJITPurchasing,PlanningandControl,andSupply-ChainAnalysis(1of2)Supplychaindescribestheflowofgoods,services,andinformationfromtheinitialsourcesofmaterialsandservicestothedeliveryofproductstoconsumers,regardlessofwhetherthoseactivitiesoccurinthesamecompanyorothercompanies.Supplychainmembersshareinformationandplan/coordinateactivities.JITPurchasing,PlanningandControl,andSupply-ChainAnalysis(2of2)Sharingsalesinformationreducesthelevelofuncertaintyaboutretaildemandandleadstothefollowing:FewerstockoutsattheretaillevelReducedmanufacturingofproductnotimmediatelyneededbyretailersFewermanufacturingordersthathavetobe“rushed”or“expedited”LowerinventoriesheldbyeachcompanyinthesupplychainInventoryManagement,MRP,andJITProductionMaterialsrequirementsplanning(MRP)isa“push-through”systemthatmanufacturesfinishedgoodsforinventoryonthebasisofdemandforecasts.JITproductionisa“demand-pull”approachandisalsocalledleanproduction.Eachcomponentinaproductionlineisproducedassoonas,andonlywhen,neededbythenextstepintheproductionline.MRPInformationInputsTodetermineoutputsateachstageofproduction,MRPusesthefollowing:ThedemandforecastsforfinalproductsAbillofmaterialsdetailingthematerials,components,andsubassembliesforeachfinalproductInformationaboutacompany’sinventoriesofmaterials,components,andproductsMRP

ProcessTakingintoaccounttheleadtimerequiredtopurchasematerialsandtomanufacturecomponentsandfinishedproducts,amasterproductionschedulespecifiesthequantityandtimingofeachitemtobeproduced.Onceproductionstartsasscheduled,theoutputofeachdepartmentispushedthroughtheproductionline.MaintainingaccurateinventoryrecordsandcostsiscriticalinanMRPsystem.JITProduction(1of2)JIT(lean)productionisa“demand-pull”manufacturingsystemthatmanufactureseachcomponentinaproductionlineassoonas,andonlywhen,neededbythenextstepintheproductionline.Demandtriggerseachstepoftheproductionprocess,startingwithcustomerdemandforafinishedproductattheendoftheprocessandworkingallthewaybacktothedemandfordirectmaterialsatthebeginningoftheprocess.JITProduction(2of2)Ascustomerinformationsystemsgetincreasinglysophisticatedandcomputingpowerallowscompaniestoprocessandanalyzelargequantitiesofdata,companiesareabletodevelopdeepinsightsintotheneedsofcustomers.Asaresult,manycompaniesarecombiningthebestfeaturesofMRPandJITsystems—anticipatingdemandchangestosomeextentbutcontinuingtooperateflexibleproductionsystemstoquicklyrespondtofluctuationsindemand.FeaturesofJITProductionSystemsProductionisorganizedinmanufacturingcells,whichareworkareaswithdifferenttypesofequipmentgroupedtogethertomakerelatedproducts.Workersarehiredandtrainedtobemultiskilled(cross-trained).Defectsareaggressivelyeliminated.Setuptimeandmanufacturingcycletimearereduced.Suppliersareselectedonthebasisoftheirabilitytodeliverqualitymaterialsinatimelymanner.CostsandBenefitsofJITProductionLowerinventorylevels,lowercarryingcostsHeightenedemphasisonimprovingqualitybyeliminatingthespecificcausesofrework,scrap,andwasteLowermanufacturingcycletimesEnterpriseResourcePlanning(ERP)Systems(1of2)ERPsystemsarefrequentlyusedinconjunctionwithJITproduction.An

ERPsystemisanintegratedsetofsoftwaremodulescoveringacompany’saccounting,distribution,manufacturing,purchasing,humanresources,andotherfunctions.Real-timeinformationiscollectedinasingledatabaseandsimultaneouslyfedintoallofthesoftwareapplications,givingpersonnelgreatervisibilityintothecompany’send-to-endbusinessprocesses.EnterpriseResourcePlanning(ERP)Systems(2of2)CompaniesbelievethatanERPsystemisessentialtosupportJITinitiativesbecauseoftheeffectithasonleadtime.Thechallenge,whenimplementingERPsystems,istostriketheproperbalancebetweenthelowercostandreliabilityofstandardizedsystemsandthestrategicbenefitsthataccruefromcustomization.PerformanceMeasuresandControlinJIT(1of2)Inadditiontotheirpersonalobservations,managersusefinancialandnonfinancialmeasurestoevaluateandcontrolJITproduction.Financialperformancemeasuressuchasinventoryturnoverratio,whichisexpectedtoincrease.PerformanceMeasuresandControlinJIT(2of2)Nonfinancialperformancemeasuresinventory,quality,andtime,suchasthefollowing:Numberofdaysofinventoryonhand,expectedtodecreaseUnitsproducedperhour,expectedtoincreaseNumberofunitsscrappedorrequiringrework/Totalnumberofunitsstartedandcompleted,expectedtoincreaseManufacturingcycletime,expectedtodecreaseTotalsetuptimeformachines/Totalmanufacturingtime,expectedtodecreaseEffectofJITSystemsonProductCostingJITSystemsReducesoverheadcostsbyreducingmaterialshandling,warehousing,andinspectionAidsinthedirecttracingofsomecostsusuallyclassifiedasindirectForthesereasons,companiesusingJITmayadoptsimplifiedproduct-costingmethodsthatarelesscostlytooperatethanthetraditionalcostingsystemsdescribedinChapters4,7,8,and18.We’lllooknextattwoofthesemethods:backflushcostingandleanaccounting.BackflushCosting(1of3)Traditionalnormalorstandard-costingsystemsusesequentialtrackinginwhichtherecordingofthejournalentriesoccursinthesameorderasactualpurchasesandprogressinproduction.Asareview,thefourstagesareasfollows:PurchaseofDirectMaterials&IncurringofConversioncosts*ProductionresultinginWIPCompletionofgoodfinishedunitsofproduct*Salesoffinishedgoods**IndicatesatriggerpointforjournalentriesBackflushCosting(2of3)Backflushcostingomitsrecordingsomeofthejournalentriesrelatingtothestagesfromthepurchaseofdirectmaterialstothesaleoffinishedgoods.Becausesomestagesareomitted,thejournalentriesforasubsequentstageusenormalorstandardcoststoworkbackwardto“flushout”thecostsinthecycleforwhichjournalentrieswerenotmade.Wheninventoriesareminimal,asinJITproductionsystems,backflushcostingsimplifiescostingsystemswithoutlosingmuchinformation.BackflushCosting(3of3)BackflushcostingdoesnotcomplywithGAAP.However,inventorylevelsmaybeimmaterial,negatingthenecessityforcompliance.Backflushcostingdoesnotleaveagoodaudittrail—theabilityoftheaccountingsystemtopinpointtheusesofresourcesateachstepoftheproductionprocess.Theabsenceofsizableamountsofmaterialsinventory,work-in-processinventory,andfinished-goodsinventorymeansmanagerscankeeptrackofoperationsbypersonalobservations,computermonitoring,andnonfinancialmeasures.LeanAccountingAnothersimplifiedproductcostingsystemthatcanbeusedwithJIT(orleanproduction)systemsisleanaccounting.WhenacompanyutilizesJITproduction,ithastofocusontheentirevaluechainofbusinessfunctions(fromsupplierstomanufacturerstocustomer)inordertoreduceinventories,leadtimes,andwaste.Theresultingimprovementsinthevaluechainhaveledso