speeches · January 25, 2018
Regional President Speech
James Bullard · President
DOES A LOW-INTEREST-RATE
REGIME HARM SAVERS?
JamesBullard
PresidentandCEO
NonlinearModelsinMacroeconomicsandFinanceforan
UnstableWorld
NorgesBank
Jan. 26,2018
Oslo,Norway
Anyopinionsexpressedherearetheauthor’sanddonotnecessarilyreflectthoseoftheFOMC.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Overview
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
THIS TALK
ThisacademictalkwaspreviouslypresentedinLondon,UK,in
July2017,inSanJose,CostaRica,inAugust2017,andatthe
AdvancedWorkshopforCentralBankers—Northwestern
University,inSeptember2017.
Theresultsherearepreliminaryandtheoreticalinnature.
Feedbackiswelcome.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Low Interest Rates and Saving
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
LOW INTEREST RATES AND SAVING
Sincethe2007-2009financialcrisisandrecession,realand
nominalinterestratesinadvancedeconomieshavebeen
exceptionallylowcomparedwithpostwarnorms.
Icallthisa“low-interest-rateregime.”
Acriticismofmonetarypolicyinadvancedeconomiesfollowing
thecrisishasbeenthatthelow-interest-rateregimehasbeen
detrimentalforsavers.
Thispresentationsuggeststhatthelow-interest-rateregimemay
notbe“harmfultosavers.”
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
LOW INTEREST RATES EMPIRICALLY
FIGURE: Source:FederalReserveBoard,U.S.DepartmentoftheTreasury,
BankofEngland,EuropeanCentralBankandJapan’sMinistryofFinance.
Lastobservation:Jan.22,2018.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
THE LINE OF ARGUMENT
Inthemodelpresentedhere,householdcreditmarketswillplay
anessentialrole.
Thereareno“stickyprices.”Instead,thekeyfrictioninthe
economyisnon-statecontingentnominalcontracting(NSCNC)in
householdcreditmarkets.
Monetarypolicywillbeabletorepairthisfrictionentirelyby
usingaversionofnominalGDPtargeting.
Therewillbeanaggregateproductivityshockfollowinga
regime-switchingstochasticprocess,yieldinga
high-real-interest-rateandalow-real-interest-rateregime.
Mainresult: Undertheoptimalmonetarypolicy,theallocationof
resourceswillbefirst-bestintratemporallyineitherthehighorthelow
regime.
Inthissense,alow-interest-rateregimewillnotbedetrimentalto
savers(oranyotherhouseholds).
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Credit Market Friction
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
HOUSEHOLD CREDIT IN A DSGE MODEL
Istudyaneconomywithalargeprivatecreditmarketthatis
essentialtogoodmacroeconomicperformance.
Ifthehouseholdcreditmarketisnotworkingproperly,some
householdswillconsumemuchlessthanothers.
TheNSCNCfrictionmeansthismarketwillnotworkwellonits
own.
Theroleofmonetarypolicywillbetorepairthisfrictionby
restoringcompletemarkets.
IignoreZLBissuesinthistalk. Seethecompanionpaperby
Azariadis,Bullard,SinghandSuda(2015),availableonmyweb
page.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
INCOME AND WEALTH INEQUALITY
Thereisalotofincomeandwealthinequalityinthisstylized
model.
Theroleofcreditmarkets,iftheyworkcorrectly,willbeto
reallocateunevenincomeacrossthelifecycleintoperfectlyequal
percapitaconsumption.
Themodelequilibriumwillnaturallyrank:
thewealthGinicoefficient>theincomeGinicoefficient>the
consumptionGinicoefficient.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
HOW LARGE ARE THESE MARKETS?
AccordingtoMianandSufi(AER,2011),theratioofhousehold
debttoGDPintheU.S.wasabout1.15beforeitballoonedto
1.65duringthe2000s.
Intoday’sdollars,thatwouldbeequivalenttogoingfromabout
$19.5trilliontoabout$28trillioninhouseholddebt,comprised
mostlyofmortgagedebt.
Disruptingthesemarketsmightbequitecostlyfortheeconomy,
sotheNSCNCfrictioncouldbequiteimportant.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Environment
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
SYMMETRY ASSUMPTIONS
Imakeasetofimportant“symmetryassumptions”sothatwe
canbetterunderstandtheequilibriumofthemodelevenwith
substantialheterogeneity.
Theseassumptionsinvolvethesymmetryofthelifecycle
productivityendowmentpatternofthehouseholds,alongwith
logpreferences,nodiscounting,andnopopulationgrowth.
Theseassumptionshelpdelivertheresultthatintheequilibrium
Istudy:
Therealinterestrateisexactlyequaltotheoutputgrowthrateatevery
date,eveninthestochasticeconomy.
Thisinturncreatesasetofeasytounderstandbaselineresults
forthiseconomy.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
LIFE CYCLE MODELS
Generalequilibriumlifecycleeconomy=many-period
overlappinggenerations.
Keyvariablesareprivately-issueddebt,realinterestratesand
inflation.
Thinkofprivately-issueddebt=“mortgage-backedsecurities.”
Thistalkhasinelasticlaborsupply. Elasticlaborsupplycanbe
added—formoreonthis,seethecompanionpaperbyBullard
andSingh(2017),availableonmywebpage.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
ENVIRONMENT DETAILS
ThemodelisastandardT+1-periodsDSGElife-cycle
endowmenteconomy.
Anewgenerationofidenticalhouseholdsisbornateachdate.
HouseholdsliveforT+1periods. AnyT 2willwork;Iprefer
(cid:21)
T+1=241(quarterly);oddvaluesareconvenient.
ThemonetarypolicymakerascontrollingthepricelevelP(t)
directly. Foramoreelaborateversionwithexplicitmoney
demand,seeAzariadis,Bullard,Singh,andSuda(2015).
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
PREFERENCES
Allparticipanthouseholdsenteringtheeconomyatdatethave
logpreferenceswithnodiscounting
T
∑
V =E lnc (t+j),
t t t
j=0
wherec (t+j) >0isthedatet+jconsumptionofthe
t
householdbornatdatet.
Householdsthatenteredtheeconomyatpreviousdateshave
similarpreferencesandcarryanet-asset-holdingpositioninto
datet.Householdsentertheeconomyandleavetheeconomy
withzeronetassets.
Otherassumptions: Within-cohortagentsareidentical,no
populationgrowth,nocapital,nodefault,flexibleprices,no
borrowingconstraints.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
LIFE-CYCLE PRODUCTIVITY
Allparticipanthouseholdsareendowedwithanidentical
productivityprofileovertheirlifetime.
Theprofilebeginsatalowvalue,risestoapeakinthemiddle
periodoflife,andthendeclinestothelowvalue.
Iassumethe“lowvalue”isboundedawayfromzeroforthis
talk.
Theproductivityprofileissymmetric.
Agentscanselltheirproductivityunitsavailableatdatetinthe
labormarketatthecompetitiverealwage.
Thecross-sectionalincomedistributionintheeconomyisthis
profilemultipliedbytherealwageatthatdate.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
LIFE-CYCLE PRODUCTIVITY = CROSS SECTION
1.0
0.8
0.6
0.4
0.2
50 100 150 200
FIGURE: Aschematicproductivityendowmentprofileforcreditmarket
participantsalsorepresentsthecrosssectionofhouseholdsatdatet.The
profileissymmetricandpeaksinthemiddleperiodofthelifecycle.About
50percentofthehouseholdsearn75percentofthelaborincomeinthecredit
sectorforη=1.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
KEY FRICTION: NSCNC
Loansaredispersedandrepaidintheunitofaccount—thatis,in
nominalterms—andarenotcontingentonincomerealizations.
Therearetwoaspectstothisfriction:
Thenon-statecontingentaspectmeansthatrealallocationswillbe
perturbedbythisfriction,and
Thenominalaspectmeansthatthemonetaryauthoritymaybeable
torepairthedistortion.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
STOCHASTIC STRUCTURE
AggregaterealoutputisproducedasY(t) =Q(t)L(t),where
L(t)isthelaborinputandQ(t)istheleveloftechnology.
ThetechnologyQ(t)improvesatastochasticrateλ(t,t+1).
Thecompetitiverealwageperproductivityunit,w(t),isthen
givenby
w(t+1) = λ(t,t+1)w(t), (1)
wherew(0) >0.
Iwillmakeassumptionsconcerningλ(t,t+1)suchthatthe
economygrowsonaverage.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
REGIME SWITCHING
IfollowBullardandSingh(IER,2012,Section2.4)todefinea
two-stateregime-switchingprocessforλ.
Thereisahigh-growthstatewithmeanλH andalow-growth
statewithmeanλL,suchthat1< λL < λH.
Withineachregime,thereisadditivenoisedescribedbyσ(cid:101)(t),
whereσisascalefactorand(cid:101)(t) i.i.d.N(0,1).
(cid:24)
Alatentvariables(t)determinestheregimeandfollowsa
first-orderMarkovprocess.
Theresultingprocessforλ(t,t+1)canbewrittenasanAR(1)
processwithanonstandarderrorterm.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
TIMING PROTOCOL
Atthebeginningofdatet,naturemovesfirstandchooses
λ(t 1,t),whichimpliesavalueforw(t).
(cid:0)
Thepolicymakermovesnextandchoosesavaluefortheprice
level,P(t).
Householdsthendecidehowmuchtoconsumeandsave.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
NOMINAL INTEREST RATE
Participanthouseholdscontractbyfixingthenominalinterest
rateoneperiodinadvance.
Thenon-statecontingentgrossnominalinterestrate,thecontract
rate,isgivenby
c (t) P(t)
Rn(t,t+1) (cid:0) 1 =E t c ( t t+1)P(t+1) . (2)
(cid:20) t (cid:21)
Thisratedependsontheexpectedgrossrateofconsumption
growthandtheexpectedgrossrateofinflation.
IntheequilibriumIstudy,consumptiongrowthratesarethe
sameforallhouseholds,sothisconditionisalsothesameforall
thehouseholdsbornatpreviousdates.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
COMPLETE MARKETS WITH NSCNC
Thecountercyclicalpricelevelpolicyruledeliverscomplete
marketsallocations:
Rn(t 1,t)
P(t) = (cid:0) P(t 1), (3)
λr(t 1,t) (cid:0)
(cid:0)
whereλrindicatesarealizationoftheshockandRnisthe
expectationgiveninthepreviousslide.
ThisissimilartoSheedy(BPEA,2014)andKoenig(IJCB,2013).
Giventhispolicyrule,householdswillconsumeequalamounts
ofavailableproductioninthecreditsector. Thisis“equityshare
contracting,”whichisoptimalunderhomotheticpreferences.
Thispricelevelrulerendersthehouseholds’date-tdecision
problemdeterministicbecauseitperfectlyinsuresthehousehold
againstfutureshockstoincome.
Consumptionandassetholdingsfluctuatefromperiodto
period,butinproportiontothevalueofw(t).
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
STATIONARY EQUILIBRIA
Welett ( ∞,+∞).
2 (cid:0)
Weonlyconsiderstationaryequilibriaundertheperfectly
crediblepolicyrulegoverningP(t).
WeletR(t)bethegrossrealrateofreturninthecreditmarket.
Stationaryequilibriumisasequence f R(t),P(t) gt + = ∞ ∞ suchthat
marketsclear,householdssolvetheiroptimizationp(cid:0)roblems,
andthepolicymakercrediblyadherestothestatedpolicyrule.
Thekeyconditionisthatnetaggregateassetholding,A(t),nets
outamongparticipanthouseholds.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Graphs
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
LABOR INCOME CHANGES IN CROSS SECTION
1.0
0.8
0.6
0.4
0.2
50 100 150 200
FIGURE: Howlaborincomechangesacrosscohortswhentherealwage
increases10percentforη=1.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
NET ASSET HOLDING IN CROSS SECTION
15
10
5
50 100 150 200
5
10
15
FIGURE: Netassetholdingbycohortalongthecompletemarketsbalanced
growthpathwithη=1.Borrowing,thenegativevaluestotheleft,peaksat
stage60ofthelifecycle(age~35),whilepositiveassetspeakatstage180of
thelifecycle(age~65).About25percentofthepopulationholdsabout75
percentoftheassets.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
CHANGE IN NET ASSET HOLDING IN CROSS SECTION
20
10
50 100 150 200
10
20
FIGURE: Hownetassetholdingchangesbycohortwhentherealwage
increasesby10percentwhenη=1.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
CONSUMPTION IN CROSS SECTION
1.0
0.8
0.6
0.4
0.2
50 100 150 200
FIGURE: Schematicrepresentationofconsumption,theflatline,versuslabor
income,thebell-shapedcurve,bycohortalongthecompletemarkets
balancedgrowthpathwithw(t)=1andη=1.Theprivatecreditmarket
completelysolvesthepoint-in-timeincomeinequalityproblem.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
CHANGE IN CONSUMPTION IN CROSS SECTION
1.0
0.8
0.6
0.4
0.2
0 50 100 150 200
FIGURE: Howlaborincomeandconsumptionchangebycohortwhenthe
realwageincreasesby10percentwithη=1.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Complete Markets
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
COMPLETE MARKETS VIA NGDP TARGETING
Thiseconomycouldbemiredinthelow-interest-rateregimefor
alongtime,dependingonassumptionsconcerningthe
persistenceoftheproductivityregimes.
Nevertheless,monetarypolicycandeliverfirst-best
intratemporalallocationsviathepricelevelruledescribedearlier
whichinduces“equitysharecontracting.”Thisoccursbothwith
regimesandacrossregimes.
ThepolicymakeriscompletelymitigatingtheNSCNCfrictionand
restoringtheWickselliannaturalrateofinterest.
Thereisnosenseinwhichsaversare“hurt”inthe
low-interest-rateregime(norareborrowers“helped”).
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
CAVEATS
Thepolicymakerhereisallowedtoobservetheshockandthen
offsetitwiththeappropriatesettingforP(t). Thisisunrealistic,
butsimilartobaselineNewKeynesianmodelsinwhich
policymakerscanappropriatelyoffsetincomingshocks.
Thelow-real-interest-rateregimeisassociatedwithaslowerrate
ofgrowthinrealwagesandrealoutput. Householdswould
ratherbeinthehighergrowthregimeinthissense. Butthe
productivitygrowthregimeistakenasanexogenousprocess
chosenbynaturehere.
Monetarypolicycannotswitchtheeconomytothehigh-growth
regime,butitcanconductanoptimalpolicygiventheregime.
Monetarypolicycanbeuseful,butnotsousefulastocreatehigh
realgrowth.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
MORE CAVEATS
Ifocusonanequilibriumwheretherealinterestrateequalsthe
outputgrowthrateeveryperiodinthestochasticeconomy.
Theremaybeotherequilibria.
Resultswouldstillholdifthereweretwoormorelifetime
productivityprofiles,allowingforintracohortincomeinequality.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Perceptions
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
INACCURATE PERCEPTIONS OF REGIMES
Inthispresentation,thepolicymakerandtheprivatesector
agentshaverationalexpectations,meaningtheyunderstandthe
natureoftheregime-switchingprocessdrivingtheeconomy.
Whatiftheyhadamisspecifiedmodelinwhichtheyexpected
theeconomytoreturntoafixedmean?
Itremainsforfuturereseachtounderstandhowtheseresults
maybealteredinthisscenario.
Nevertheless,thismaybeoccurringinactualU.S.monetary
policy.
ThefollowingchartsillustratethispossibilityusingrecentU.S.
data.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
POLICYMAKER PERCEPTIONS
FIGURE: Source:FederalReserveBoardandauthor’scalculations.Last
observation:December2017.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
PRIVATE SECTOR PERCEPTIONS
FIGURE: Source:FRBofPhiladelphiaandauthor’scalculations.Last
observation:2017-Q3.
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
Conclusions
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
CONCLUSIONS
Thedesirebehindmanyactualpolicychoicesoverthelast
severalyearshasbeentohelphouseholdcreditmarkets,
especiallymortgagemarkets,performbetter.
Thecreditmarketherecanbeinterpretedasaresidential
mortgagemarket—“mortgage-backedsecurities.”
MonetarypolicycanalleviatetheNSCNCfrictionandrestore
thesmoothfunctioningofthecreditmarket.
Thispolicyresultremainseveniftheeconomyswitches
infrequentlybetweenhigh-andlow-real-interest-rateregimes.
Onesentencesummary: “Onecannotreadwelfareimplications
offoftheobservationoftherealinterestratealone.”
INTRO LOWINTERESTRATES&SAVING FRICTION ENVIRONMENT GRAPHS POLICY PERCEPTIONS END
NATURAL VS. UNNATURAL REAL INTEREST RATES
Herethemonetarypolicymakercanrestorethefirst-best
intratemporalallocationofresourcesbymovingthepricelevelto
achievetheWickselliannaturalrealrateofinterestforthe
economy,withthenaturalrateitselffluctuatingaccordingtoa
regime-switchingprocess.
Thisanalysiscanprovideagoodbaselineforthinkingaboutthe
currentsituationinadvancedeconomiesiflowrealinterestrates
canbemostlyattributedtofactorsexogenoustomonetarypolicy.
However,whatiflowrealinterestratesareattributedtomonetary
policyitself (asmanycriticsnodoubtwouldargue)?
Thenitmaybethecasethatthoseratesaredistortionaryandcould
hurtsomesegmentsofsociety.Thatcouldbeanalyzedhere,sayby
havingthepolicymakersetthe“wrongvalueforP(t)”each
period.Thatwouldrequireacomputationalsolutionasopposedto
thepencil-and-papersolutionusedinthistalk.
Cite this document
APA
James Bullard (2018, January 25). Regional President Speech. Speeches, Federal Reserve. https://whenthefedspeaks.com/doc/regional_speeche_20180126_james_bullard
BibTeX
@misc{wtfs_regional_speeche_20180126_james_bullard,
author = {James Bullard},
title = {Regional President Speech},
year = {2018},
month = {Jan},
howpublished = {Speeches, Federal Reserve},
url = {https://whenthefedspeaks.com/doc/regional_speeche_20180126_james_bullard},
note = {Retrieved via When the Fed Speaks corpus}
}