Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
House Prices and Consumer Spending David Berger, Veronica Guerrieri, - - PowerPoint PPT Presentation
House Prices and Consumer Spending David Berger, Veronica Guerrieri, - - PowerPoint PPT Presentation
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix House Prices and Consumer Spending David Berger, Veronica Guerrieri, Guido Lorenzoni, Joe Vavra BBLM, Departimento del Tesoro Giugno 2017 Motivation Baseline
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Consumption Decline in Great Recession
5 10 0.96 0.98 1 1.02 1.04 1.06 1.08 1.1 1.12 1.14
Total Consumption
1973-75 1980 1982-83 1990-91 2001 2007-09 5 10 0.95 1 1.05 1.1
Non-Durable Goods
5 10 0.98 1 1.02 1.04 1.06 1.08 1.1 1.12 1.14 Quarter Since Recession Start
Services
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Consumption Response to House Prices in the Data
- deep consumption decline in Great Recession
- growing literature points to large decline in housing wealth
- various measures of consumption respond strongly to
house price movements under various identifications:
- Campbell and Cocco (2007): UK non-durable exp (≈ 1.22)
- Case, Quigley and Shiller (2013): state-level data
(0.03−0.18)
- Mian, Rao, and Sufi (2013): county Mastercard spending +
autos spending (0.13−0.26)
- Stroebel and Vavra (2015): Nielsen homescan spending
- puzzle relative to standard PIH model (Sinai and Souleles)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Question
broad question: can consumption models rationalize this evidence? in particular:
- can a standard model with incomplete markets work?
- what are the channels?
- does the level/distribution of household debt matter?
- can we rationalize the recent boom-bust episode?
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Results
- wide class of Bewley-type of models ⇒ simple formula:
∆Cit
∆Pt Pt
= MPCit(1−δ)PtHit−1
- holds exactly with strong assumptions, but typically a
accurate approximation
- estimate our formula in the data using BPP approach
implies large elasticities consistent with:
- calibrated model
- other empirical estimates
- general equilibrium exercise: boom-bust episode
- main shock: expected housing appreciation shock
- consumption response dominated by partial equilibrium
- GE effect important for residential investment and for bust
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Set up
- households indexed by i live J = 60 periods
- work for Jy = 35 periods and retired for Jo = 25
- jit = age of household i at time t
- two assets: a risk-free asset (Ait) and housing (Hit)
- risk-free asset yields interest r
- housing stock yields housing services one for one
- depreciation rate δ and exogenous house prices Pt
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Preferences
- for household i at time t with jit < J:
U(Cit,Hit) = (Cα
it H1−α it
)1−σ 1−σ
- bequest motive for jit = J:
U(Cit,Hit)+β Ψ 1−σ Γi +(1−δ)Pt+1Hit +(1+r)Ait PXt+1 1−σ , Γi = human wealth of offspring PXt+1 = price index that converts nominal into real wealth
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Constraints
- budget constraint
Cit +PtHit +Ait = Yit +(1−δ)PtHit−1 +(1+r)Ait−1
- borrowing constraint
−(1+r)Ait ≤ (1−θ)(1−δ)Pt+1Hit
- income process when agent works:
Yit = exp{χ(jit)+zit} where χ(jit) age-dependent component and zit = ρzit−1 +ηit
- social security process as in Guvenen and Smith (2014)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Benchmark
- special case = permanent income:
- 1. no income uncertainty
- 2. no borrowing constraint
- 3. constant house prices
- assume
β (1+r) = 1 and Ψ = (1−β)−σ
- perfect consumption smoothing:
Ct = α (1−β)
- J
∑
j=0
(1+r)−jYt+j +(1−δ)PHt−1 +(1+r)At−1
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Benchmark: Some Numbers
- elasticity of consumption to house prices
dC C /dP P = (1−δ)PHt−1 ∑J
j=0(1+r)−jYt+j +(1−δ)PHt−1 +(1+r)At−1
- set r = 2.5%, then human wealth is ≈ Y/r = 40Y
- set (1−δ)PH = 2.15Y and A = −0.32Y (2001 SCF)
elasticity = 0.0514
- suppose household debt goes up by 0.5Y so that
A = −0.82Y elasticity = 0.0520
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Benchmark: Take Out
- implication 1:
aggregate elasticity is small relative to empirical literature
- implication 2:
aggregate elasticity minimally affected by household debt
- implication 3:
the old are the ones with higher elasticities
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
General Model: Simple Formula
- Proposition: individual consumption response to a
permanent change in house price: ∆Cit ∆Pt/Pt = MPCit(1−δ)PtHit−1
- 3 key assumptions:
- 1. liquid housing wealth
- 2. Cobb-Douglas/CRRA preferences
- formula can be extended for CES and θ = 0
- results robust numerically for CES with θ > 0
- 3. house prices follow a random walk (special case: constant)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Interpretation
- important implication: larger consumption response the
larger correlation of MPC and housing values
- house price increases affect C in 4 ways:
- 1. endowment effect: existing house worth more (C ↑)
- 2. income effect: housing more expensive (C ↓)
- 3. substitution effect: housing relatively more exp. (C ↑)
- 4. collateral effect: relaxed borrowing constraint (C ↑)
- our formula: consumption response represented as pure
endowment effect! ⇒ effects 2-4 cancel out
- however all effects are large in isolation (more later ...)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Calibration
- annual model → interest rate r = 2.4%
- intertemporal elasticity σ = 2
- housing depreciation rate δ = 2.2% (BEA data)
- collateral constraint θ = 0.25 (minimum down payment)
- income process using PSID data:
- life-cycle component to fit regression of earnings on age (as
Kaplan and Violante 2010)
- temporary component: ρ = 0.91, σ = 0.21 (as Floden and
Linde 2001)
- remaining parameters target life-cycle profiles of housing
and liquid wealth in 2001 SCF data (9 age bins)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Model Fit
25 30 35 40 45 50 55 60 65 70 1 1.5 2 2.5 3 3.5
Housing wealth
Age 25 30 35 40 45 50 55 60 65 70 −1 1 2
Liquid wealth net of debt
Age Model SCF 2001
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Elasticities over the Life Cycle
30 35 40 45 50 55 0.35 0.4 0.45 0.5 0.55
Age
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Understanding the Life Cycle
25 30 35 40 45 50 55 1 1.5 2 2.5 3 3.5
Housing over the lifecycle
Age
25 30 35 40 45 50 55 0.05 0.1 0.15 0.2 0.25 0.3 MPC over the lifecycle
Age
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Decomposition
Age 30 35 40 45 50 55
- 0.2
- 0.1
0.1 0.2 0.3
Substitution effect Income effect Collateral effect Endowment effect
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
More on Decomposition
- substitution, collateral, and "net-wealth" effect of similar
size
- "net-wealth" effect = endowment + income effect
- borrowing constraints in our model ⇒ net-wealth effect > 0
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
More on Decomposition
- substitution, collateral, and "net-wealth" effect of similar
size
- "net-wealth" effect = endowment + income effect
- borrowing constraints in our model ⇒ net-wealth effect > 0
- Comparison to existing "small wealth effects" models:
- 1. PIH:
- Collateral effect = 0
- Net-wealth effect ≃ 0
- 2. Sinai and Souleles (2005):
- Collateral effect = 0
- Net-wealth effect = 0
- Substitution effect = 0
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Some Implications
- 1. all 4 effects are large in isolation
consistent with DeFusco (2015): large collateral channel
- 2. larger consumption responses when both MPC and PH
are large consistent with Mian, Rao, Sufi (2013): biggest effects for most levered
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Baseline: Take Out
- implication 1:
aggregate elasticity over working life is large = 0.47
- implication 2:
aggregate elasticity affected by household debt distribution
- implication 3:
the young are the ones with higher elasticities because are more levered (Attanasio et al. 2009)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Adjustment Costs
- with liquid housing wealth housing adjusts too much
- ⇒ introduce adjustment costs
- fixed cost of trading housing proportional to house value
κit = F ·PtHit−11Hit=Hit−1
- adjustment cost F = .05
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Elasticities over the Life Cycle
25 30 35 40 45 50 55 60 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 Age Aggregate C Elasticity Approximation
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Rental Option
- so far everybody is homeowner...
- while US homeownership rate is roughly 2/3
- → introduce the option to rent
- flow cost of renting to match the homeownership rate
- rent/price ratio is constant trade-off:
- advantage: keep savings in liquid assets
- disadvantage: renting is more costly and rental house
cannot be used as collateral
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Calibration
Shock size matters since MPC non-linear:
25 30 35 40 45 50 55 60 65 70
Age
2 4
Housing Wealth
25 30 35 40 45 50 55 60 65 70
Age
- 2
2
Liquid wealth net of debt
25 30 35 40 45 50 55 60 65 70
Age
0.5 1
Homeownership Rate
Model SCF 2001
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Elasticities over the Life Cycle
25 30 35 40 45 50 55 60 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
age
Elasticity
rental option approx no rental option approx
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Understanding the Life Cycle
25 30 35 40 45 50 55 60 0.5 1 1.5 2 2.5 3
Housing over the lifecycle
age
25 30 35 40 45 50 55 60 0.2 0.4 0.6 0.8 MPC over the lifecycle
age
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
More Dimensions of Heterogeneity
10 20
Income Bin
0.2 0.4 0.6
Elasticity Approximation
10 20
Housing Bin
0.2 0.4 0.6
Elasticity Approximation
10 20
Voluntary Equity Bin
0.5 1
Elasticity Approximation
30 40 50
Age
0.1 0.2 0.3 0.4 0.5
Elasticity Approximation
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Accuracy
- 0.5
0.5 1 1.5 2 Elasticity Approximation
- 0.5
0.5 1 1.5 2 Elasticity
R2 for a simple linear regression is 0.95.
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Comments
- sufficient statistic still works approximately pretty well
- aggregate elasticity drops to .24 (working life)
- why?
- mechanical effect because renters do not respond to
prices, but also selection!
- MPC tend to be bigger for the young
- the old have accumulated a lot of liquid wealth!
- BUT in a model with rental option the young tend to rent
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
More Realistic Mortgages
- we model mortgages as one-period loans subject to
collateral constraints
- two steps towards more realistic loans:
- 1. introduce costly equity extraction
- if households increase their debt level they need to pay a
fixed cost
- 2. introduce asymmetric adjustment to the borrowing limit
- when house price falls lenders cannot force households to
put up additional collateral
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Results for More Realistic Mortgages
25 30 35 40 45 50 55 60 0.1 0.2 0.3 0.4 0.5 Age
Costly Refinancing Model
Aggregate C Elasticity Approximation 25 30 35 40 45 50 55 60 0.1 0.2 0.3 0.4 0.5 Age
Asymmetric Mortgage Model
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Full Model: Take Out
- implication 1:
aggregate elasticity is sizeable = 0.24
- implication 2:
aggregate elasticity still affected by household debt level and distribution
- implication 3:
- ur simple formula still a good approximation
- implication 4:
rental option matters a lot, adjustment cost and mortgage simplifications not
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Estimation
- we estimate the sufficient-statistic formula with micro data
→ new measure independent of calibration
- we follow Blundell, Pistaferri and Preston (2008) to
estimate MPC to temporary shocks using PSID data
- BPP estimator: instrument for change in income with
change in future income
- do this separately for different housing bins to estimate
MPC ×H in data
- our estimation gives an average elasticity of 0.33 (similar to
Mian, Rao and Sufi (2013))
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Elasticity in the PSID
1 2 3 4 5
Income Bin
- 0.5
0.5 1 2 4
Housing Bin
0.5 1 2 4 6 8 10
Voluntary Equity Bin
0.5 1 30 40 50 60
Age
0.5 1
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Boom-Bust Experiment
- simple general equilibrium exercise to think about recent
house price boom-bust episode in the US
- partial equilibrium model has counterfactual implications
for housing demand and debt
- ⇒ new shock to expectations about future house price
appreciation Et
- Pt+j
- = Pt exp
- gt
1−λ j 1−λ
- for j = 1,2,...
- set λ = .5 and choose {gt} and housing supply to match
residential investment and housing market clearing at prices from Shiller (2015)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
With g shocks (blue) vs no g shocks (red)
2000 2005 2010 0.6 0.8 1 1.2 1.4 1.6 House price 2000 2005 2010 % 0.5 1 1.5 Expected price growth 2000 2005 2010 % deviation from steady state
- 5
5 Consumption baseline g=0 2000 2005 2010 % deviation from steady state
- 300
- 200
- 100
100 200 300 Residential investment
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Effects of Changing g
g (in %)
- 2
- 1.5
- 1
- 0.5
0.5 1 1.5 2
- 4
- 2
2 4 Consumption (% change) g (in %)
- 2
- 1.5
- 1
- 0.5
0.5 1 1.5 2
- 2000
- 1000
1000 2000 3000 Residential investment (% change)
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Endogenous Changes in Wealth Distribution
2006 2007 2008 2009 2010 2011 2012 2013 % deviation from steady state
- 16
- 14
- 12
- 10
- 8
- 6
- 4
- 2
Consumption
baseline starting at initial steady state distribution
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Final Remarks
- we explore models with incomplete markets to think about
the response of consumption to changes in house prices
- with liquid housing, this response = MPC ·(1−δ)H
- formula works approximately well also in more general
model
- model delivers large elasticities in line with empirical
literature
- estimate formula with macro data and find similar results
- GE exercise with shocks to price growth expectations to
match residential investment
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Proof: step 1
- state (W,s) where W ≡ total wealth and s ≡ (z,j)
- for all j < J:
Vt(W,s) = max
C,H,A,W ′ U(C,H)+βE[Vt+1(W ′,s′)|s]
subject to C +PtH +A = W +Y(s) W ′ = (1−δ)Pt+1H +(1+r)A (1−θ)(1−δ)Pt+1H +(1+r)A ≥ 0
- for j = J +1, bequest motive:
Vt(W,s) = Ψ 1−σ Γ(s)+W ˆ PXt 1−σ
Motivation Baseline Model Full Model Empirics Boom-Bust Conclusions Appendix
Proof: step 2
- let ˜
H = PH: V(W,s) = max
C,˜ H,A,W ′ P(σ−1)(1−α)U(C, ˜
H)+βE[V(W ′,s′)] subject to C + ˜ H +A = W +Y(s) W ′ = (1−δ) ˜ H +(1+r)A (1−θ)(1−δ) ˜ H +(1+r)A ≥ 0
- ⇒ consumption policy C(W,s) does not depend on P!
- ⇒ dC(W,s)/dP = dC(W,s)/dW ·dW/dP