宏观经济学-课件30money inflation

30MoneyGrowthandInflationTheMeaningofMoneyMoneyisthesetofassetsinaneconomythatpeopleregularlyusetobuygoodsandservicesfromotherpeople.THECLASSICALTHEORYOFINFLATIONInflationisanincreaseintheoveralllevelofprices.通货膨胀是物价水平普遍而持续的上升。按照通货膨胀的严重程度，可以将其分为三类：

第一，爬行的通货膨胀，又称温和的通货膨胀，其特点是通货膨胀率低而且比较稳定。

第二，加速的通货膨胀，又称奔驰的通货膨胀，其特点是通货膨胀率较高（一般在两位数以上），而且还在加剧。

第三，超速通货膨胀，又称恶性通货膨胀，其特点是通货膨胀率非常高（标准是每月通货膨胀率在50％以上）而且完全失去了控制。Hyperinflationisanextraordinarilyhighrateofinflation.THECLASSICALTHEORYOFINFLATIONInflation:HistoricalAspectsOverthepast60years,priceshaverisenonaverageabout5percentperyear.Deflation,meaningdecreasingaverageprices,occurredintheU.S.inthenineteenthcentury.HyperinflationreferstohighratesofinflationsuchasGermanyexperiencedinthe1920s.德国20年代初的物价，曾在每49小时增加一倍；40年代初的希腊被德国占率时，物价每28小时上升一倍；匈牙利战后曾每15小时增加一倍。这种极端例子一般在战事发生，即使近数十年亦时有出现。1993年10月至1994年1月，南斯拉夫的通胀就曾每16小时增加一倍；乌克兰、秘鲁、墨西哥、阿根廷、巴西等，亦在80或90年代面对严重通胀。THECLASSICALTHEORYOFINFLATIONInflation:HistoricalAspectsInthe1970spricesroseby7percentperyear.Duringthe1990s,pricesroseatanaveragerateof2percentperyear.中国的通货膨胀历史中国的通货膨胀历史经济增速与通胀物价与猪肉伴随着通胀……结果……物价与M2物价与M2困惑……THECLASSICALTHEORYOFINFLATIONThequantitytheoryofmoneyisusedtoexplainthelong-rundeterminantsofthepricelevelandtheinflationrate.Inflationisaneconomy-widephenomenonthatconcernsthevalueoftheeconomy’smediumofexchange.Whentheoverallpricelevelrises,thevalueofmoneyfalls.MoneySupply,MoneyDemand,andMonetaryEquilibriumThemoneysupply

isapolicyvariablethatiscontrolledbytheFed.Throughinstrumentssuchasopen-marketoperations,theFeddirectlycontrolsthequantityofmoneysupplied.MoneySupply,MoneyDemand,andMonetaryEquilibriumMoneydemandhasseveraldeterminants,includinginterestratesandtheaveragelevelofpricesintheeconomy.MoneySupply,MoneyDemand,andMonetaryEquilibriumPeopleholdmoneybecauseitisthemediumofexchange.Theamountofmoneypeoplechoosetoholddependsonthepricesofgoodsandservices.Note：凯恩斯流动性偏好理论MoneySupply,MoneyDemand,andMonetaryEquilibriumInthelongrun,theoveralllevelofpricesadjuststothelevelatwhichthedemandformoneyequalsthesupply.Figure1MoneySupply,MoneyDemand,andtheEquilibriumPriceLevelCopyright©2004South-WesternQuantityofMoneyValueofMoney,1/PPriceLevel,PQuantityfixedbytheFedMoneysupply01(Low)(High)(High)(Low)1/21/43/411.3324EquilibriumvalueofmoneyEquilibriumpricelevelMoneydemandAFigure2TheEffectsofMonetaryInjectionCopyright©2004South-WesternQuantityofMoneyValueofMoney,1/PPriceLevel,PMoneydemand01(Low)(High)(High)(Low)1/21/43/411.3324M1MS1M2MS22....decreasesthevalueofmoney...3....andincreasesthepricelevel.1.Anincreaseinthemoneysupply...ABTHECLASSICALTHEORYOFINFLATIONTheQuantityTheoryofMoneyHowthepricelevelisdeterminedandwhyitmightchangeovertimeiscalledthequantitytheoryofmoney.Thequantityofmoneyavailableintheeconomydeterminesthevalueofmoney.Theprimarycauseofinflationisthegrowthinthequantityofmoney.TheClassicalDichotomyandMonetaryNeutralityNominalvariablesarevariablesmeasuredinmonetaryunits.Realvariablesarevariablesmeasuredinphysicalunits.TheClassicalDichotomyandMonetaryNeutralityAccordingtoHumeandothers,realeconomicvariablesdonotchangewithchangesinthemoneysupply.Accordingtotheclassicaldichotomy,differentforcesinfluencerealandnominalvariables.Changesinthemoneysupplyaffectnominalvariablesbutnotrealvariables.Hume其人戴维·休谟（DavidHume，1711年—1776年），苏格兰哲学家，与约翰·洛克（JohnLocke）及乔治·贝克莱（GeorgeBerkeley）并称三大英国经验主义者。他被视为是苏格兰启蒙运动以及西方哲学历史中最重要的人物之一。26岁完成《人性论》：哲学历史上最重要的著作之一33岁完成《道德和政治论文集》43岁完成《大不列颠史》死后出版了《论自杀》、《论灵魂不朽》、《自然宗教对话录》经济思想贡献：私人财产、通货膨胀、以及国际贸易的理论私人财产不是一种自然权利，但由于资源有限，财产权利是正当的；财产不均衡分配有其合理性和正当性国际贸易的目标不是积累货币，而且是一种刺激经济发展的途径。最先提出了物价-货币流动机制。贸易顺差累积黄金-物价上升-通胀-减少出口增加进口-阻止黄金累积TheClassicalDichotomyandMonetaryNeutralityTheirrelevanceofmonetarychangesforrealvariablesiscalledmonetaryneutrality.VelocityandtheQuantityEquationThevelocityofmoneyreferstothespeedatwhichthetypicaldollarbilltravelsaroundtheeconomyfromwallettowallet.VelocityandtheQuantityEquationV=(PY)/MWhere:V=velocityP=thepricelevelY=thequantityofoutputM=thequantityofmoneyVelocityandtheQuantityEquationRewritingtheequationgivesthequantityequation:M

V

=PYVelocityandtheQuantityEquationThequantityequationrelatesthequantityofmoney(M)tothenominalvalueofoutput

(P

Y).VelocityandtheQuantityEquationThequantityequationshowsthatanincreaseinthequantityofmoneyinaneconomymustbereflectedinoneofthreeothervariables:thepricelevelmustrise,thequantityofoutputmustrise,orthevelocityofmoneymustfall.Figure3NominalGDP,theQuantityofMoney,andtheVelocityofMoneyCopyright©2004South-WesternIndexes(1960=100)2,0001,00050001,500196019651970197519801985199019952000NominalGDPVelocityM2VelocityandtheQuantityEquationTheEquilibriumPriceLevel,InflationRate,andtheQuantityTheoryofMoney

Thevelocityofmoneyisrelativelystableovertime.WhentheFedchangesthequantityofmoney,itcausesproportionatechangesinthenominalvalueofoutput(PY).Becausemoneyisneutral,moneydoesnotaffectoutput.CASESTUDY:MoneyandPricesduringFourHyperinflationsHyperinflationisinflationthatexceeds50percentpermonth.Hyperinflationoccursinsomecountriesbecausethegovernmentprintstoomuchmoneytopayforitsspending.Figure4MoneyandPricesDuringFourHyperinflationsCopyright©2004South-Western(a)Austria(b)HungaryMoneysupplyPricelevelIndex(Jan.1921=100)Index(July1921=100)Pricelevel100,00010,0001,00010019251924192319221921Moneysupply100,00010,0001,00010019251924192319221921Figure4MoneyandPricesDuringFourHyperinflationsCopyright©2004South-Western(c)Germany1Index(Jan.1921=100)(d)Poland100,000,000,000,0001,000,00010,000,000,0001,000,000,000,000100,000,00010,000100MoneysupplyPricelevel19251924192319221921PricelevelMoneysupplyIndex(Jan.1921=100)10010,000,000100,0001,000,00010,0001,00019251924192319221921TheInflationTaxWhenthegovernmentraisesrevenuebyprintingmoney,itissaidtolevyaninflationtax.Aninflationtaxislikeataxoneveryonewhoholdsmoney.Theinflationendswhenthegovernmentinstitutesfiscalreformssuchascutsingovernmentspending.TheFisherEffectTheFishereffectreferstoaone-to-oneadjustmentofthenominalinterestratetotheinflationrate.AccordingtotheFishereffect,whentherateofinflationrises,thenominalinterestraterisesbythesameamount.Therealinterestratestaysthesame.Figure5TheNominalInterestRateandtheInflationRateCopyright©2004South-WesternPercent(peryear)19601965197019751980198519901995200003691215InflationNominalinterestrateTHECOSTSOFINFLATIONAFallinPurchasingPower?Inflationdoesnotinitselfreducepeople’srealpurchasingpower.一些经济学家相信微弱的通货膨胀，比如每年2%-3%的通货膨胀是一件好事。

对于温和通货膨胀的支持是以观察到名义工资极少被降低开始的。企业不愿意削减他们工人的工资，当然，工人们也不愿意接受工资的降低。在一个零通货膨胀的世界里削减2%的工资实际上与在通胀率为5%的情况下提高工资3%是一样的。但是工人们并不这么看，削减2%的工资看起来是一种侮辱，而3%的提升毕竟也是一种提升。现实研究也证明了名义工资极少的被降低。所以，温和的通货膨胀可以使劳动力市场运转的更好。不同种类的劳动力的供求总和总是在发生变化，有时候，供给的增加或者需求的减少会让这种工人的实际工资下降。如果名义工资不下降，那么唯一的降低实际工资的方法就是借助通货膨胀，没有通货膨胀。实际工资将会停留在原来的水平上，从而导致更多的失业。由于这个原因，通货膨胀像是给劳动力市场的车轮上了油。THECOSTSOFINFLATIONShoeleathercostsMenucostsRelativepricevariabilityTaxdistortionsConfusionandinconvenienceArbitraryredistributionofwealthShoeleatherCostsShoeleathercostsaretheresourceswastedwheninflationencouragespeopletoreducetheirmoneyholdings.Inflationreducestherealvalueofmoney,sopeoplehaveanincentivetominimizetheircashholdings.ShoeleatherCostsLesscashrequiresmorefrequenttripstothebanktowithdrawmoneyfrominterest-bearingaccounts.Theactualcostofreducingyourmoneyholdingsisthetimeandconvenienceyoumustsacrificetokeeplessmoneyonhand.Also,extratripstothebanktaketimeawayfromproductiveactivities.皮鞋成本高的通货膨胀率会导致公众对存款信心的下降，比起储蓄人们也许更加愿意将货币置换成其他商品，比如房产或者黄金，以避免实际购买力的降低。这样的话，银行所持有的货币减少，银行持有的货币量直接影响着银行的利润，所以银行会提高利率来吸引储蓄。这样就导致了名义利率的上升（这个现象叫做费雪效应，前篇已经提到）。名义利率的上升又减少了实际的货币余额，如果人们都减少了所持有的货币余额，他们就必然更频繁的跑去银行存款取款。这种因为通货膨胀造成的货币持有量下降而带来的不方便用术语说就叫做“成本”，这个词源于因为常常去银行所造成的鞋底的磨损。

MenuCostsMenucostsarethecostsofadjustingprices.Duringinflationarytimes,itisnecessarytoupdatepricelistsandotherpostedprices.Thisisaresource-consumingprocessthattakesawayfromotherproductiveactivities.高通货膨胀会使企业更频繁的改变自己的报价，改变物价有时是有成本的，例如，它需要经常印刷并发送新的报价表。由于高通货膨胀率，微观经济资源配置无效率所带来的成本被称为“菜单成本”。这个词源于因为高通胀率时，餐馆需要经常的印刷新菜单。Relative-PriceVariabilityandtheMisallocationofResourcesInflationdistortsrelativeprices.Consumerdecisionsaredistorted,andmarketsarelessabletoallocateresourcestotheirbestuse.Inflation-InducedTaxDistortionInflationexaggeratesthesizeofcapitalgainsandincreasesthetaxburdenonthistypeofe.Withprogressivetaxation,capitalgainsaretaxedmoreheavily.Inflation-InducedTaxDistortionTheetaxtreatsthenominalinterestearnedonsavingsase,eventhoughpartofthenominalinterestratemerelycompensatesforinflation.Theafter-taxrealinterestratefalls,makingsavinglessattractive.举个简单的例子，你在年初购买了一定量的股票，购入价每股100元，股票一年升值12%，年底你以每股112的价格将股票售出，假设当年的通货膨胀率同样为12%，那么这一笔股票投资并没有为你赚到钱，你的实际购买力与年初你购进股票时是相同的。但在这种情况下，税收法则并没有考虑通货膨胀所带来的影响。你依然需要为你每股12元的收益缴纳个人所得税。这就在无形中加大了民众的个人所得税的负担。Table1HowInflationRaisestheTaxBurdenonSavingCopyright©2004South-WesternConfusionandInconvenienceWhentheFedincreasesthemoneysupplyandcreatesinflation,iterodestherealvalueoftheunitofaccount.Inflationcausesdollarsatdifferenttimestohavedifferentrealvalues.Therefore,withrisingprices,itismoredifficulttocomparerealrevenues,costs,andprofitsovertime.ASpecialCostofUnexpectedInflation:ArbitraryRedistributionofWealthUnexpectedinflationredistributeswealthamongthepopulationinawaythathasnothingtodowitheithermeritorneed.Theseredistributionsoccurbecausemanyloansintheeconomyarespecifiedintermsoftheunitofaccount—money.长期贷款协议一般规定名义利率，这个名义利率根据签订协议时预期的通货膨胀率来确定。如果结果证明实际通胀率与所预期的不同，债务人向债权人支付的事后实际收益就不同于双方所预期的。如果结果证明通货膨胀率高于预期，则债务人获益而债权人受损，因为债务人偿还的是贬值了的贷款。反之，如果结果证明通货膨胀率低于预期，则债权人获益而债务人受损。未预期到的通货膨胀还损害了依靠固定养老金生活的人。当工人退休时，工人和企业通常根据固定的数额签订养老金协议。那么如果通货膨胀率高于预期，那么工人的利益将受到损失。

SummaryTheoveralllevelofpricesinaneconomyadjuststobringmoneysupplyandmoneydemandintobalance.Whenthecent