Hayashi and Prescott (2002):
“The 1990s in Japan: A Lost Decade”
Takeki Sunakawa
Advanced Macroeconomics at Tohoku University
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 1 / 26
Introduction
The Japanese economy has been stuck in depression since the 1990s. The average growth of GDP per capita is 0.5% for 1991-2000.
What is the problem?
Inadequate fiscal policy, over investment in the 1980s, problems with financial intermediation, etc.
A breakdown of financial system in 1997-98 is not the cause of the problem.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 2 / 26
Introduction, cont’d
The problem is a low growth rate of total factor productivity (TFP).
The reduction of the workweek length also contributes to the low growth rates.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 3 / 26
Poor performance in the 1990s
Workweek falls in the 1998-93 period
Capital deepens...
...as the rate of return declines
Government expenditure and investment
Production function
The representative firm’s production function is given by: Yt= AtKtθ(htEt)1−θ,
where Ytis aggregate output, Atis the TFP, Ktis aggregate capital, htis hours per worker (workweek), and Etis employment.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 9 / 26
Growth accounting
Let Ntbe the working-age population and define y = Y /N , e = E/N , and x = K/Y . Then we have
Yt= AtKtθ(htEt)1−θ,
⇔ Yt1/(1−θ)= A1/(1−θ)t Ktθ/(1−θ)htEt,
⇔ Yt= A1/(1−θ)t xθ/(1−θ)t htEt,
∴ yt= A1/(1−θ)t xθ/(1−θ)t htet.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 10 / 26
Growth accounting, cont’d
Growth of output per capita is decomposed as
gyt= 1
1 − θgAt+ θ
1 − θgxt+ ght+ get, where θ = 0.362.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 11 / 26
Household’s utility
There are Nthouseholds in working age. The utility function is X∞
t=0
Nt(log ct− g(ht; zt)et) ,
where et= Et/Ntis the fraction of working households and ct= Ct/Nt is consumption per capita.
Labor is indivisible so that a person eigher works ht hours or does not work at all.
Households also choose htif they work. ztis the number of days worked and exogenously given.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 12 / 26
Household’s budget constraint
The household’s budget constraint is given by
Ct+ It ≤ wthtEt+ rtKt− τ (rt− δ)Kt− πt, It = Kt+1− (1 − δ)Kt,
where Ctis aggregate consumption, Itis aggregate investment, wtis wage rate and rt is real interest rate.
A distortionary tax is imposed at rate τ on capital income after depreciation. πt is a lumpsum tax.
Second welfare theorem does not hold.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 13 / 26
Closing the model
Resource constraint is given by
Ct+ It+ Gt= Yt.
The government’s budget constraint is implicitly obtained as Gt= τ (rt− δ)Kt+ πt.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 14 / 26
Solving the model: Firm
The representative firm maximizes its profit: (marginal cost) = (marginal product)
wt= (1 − θ)yt/(htet), rt= θyt/kt.
where yt and ktare output and capital per capita.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 15 / 26
Solving the model: Household
The household’s Lagrangean is
Lt≡ X∞ t=0
βt{Nt(log ct− g(ht; zt)et)} .
+λtNt(wthtet+ rtkt− τ (rt− δ)kt− ˜πt− ct− ntkt+1+ (1 − δ)kt) , where nt≡ Nt+1/Nt and ˜πt≡ πt/Nt.
The FOCs are
∂ct: c−t1= λt,
∂et: g(ht; zt) = λtwtht,
∂ht: g′(ht; zt) = λtwt,
∂kt+1: 1 = βλt+1 λt
(1 + (1 − τ )(rt+1− δ)) .
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 16 / 26
Solving the model: Aggregation
The resource constraint (per capita) is
ct+ ntkt+1− (1 − δ)kt+ gt= yt. The production function is
yt= Atkθt(htet)1−θ.
We have {ct, kt, yt, ht, et, λt, wt, rt} and 8 equations, so we can solve the model.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 17 / 26
Equilibrium conditions
The equlibrium conditions are summerized as ctg(ht; zt) = (1 − θ)yt/et, ctg′(ht; zt) = (1 − θ)yt/(htet), 1 = β ct
ct+1
(1 + (1 − τ )(rt+1− δ)) , ct+ ntkt+1− (1 − δ)kt+ gt= yt, yt= Atkθt(htet)1−θ,
wt= (1 − θ)yt/(htet), rt= θyt/kt.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 18 / 26
Labor disutility and hours worked
Combining the first two equations
hg′(h; z) = g(h; z),
where g(h; z) is convex in h and g(0; z) > 0 because of the fixed cost of going work. h(z) is determined separately from the rest of the model. Further, g(h) is approximated around ¯h = 40 as
g(h(z)) ≈ αh(z)¯ h . [Note what HP actually do is somewhat different.]
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 19 / 26
Indivisible labor
Why g(h) is convex and g(0) > 0? etis also the probability of employed, and the household’s utility function is
log(ct) + φ(ht)et+ φ0(1 − et),
where φ′(h) < 0 and φ′′(h) < 0 (e.g., φ(h) = A log(1 − h)). Ignoring a constant term, g(h) ≡ φ0− φ(h).
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 20 / 26
How hours worked are determined
Detrending
Let Zt≡ At1−θ1 and define
˜
ct≡ ct/Zt, ˜kt≡ kt/Zt, y˜t≡ yt/Zt, γt≡ Zt+1/Zt, ψt≡ gt/yt, nt≡ Nt+1/Nt. Finally, we have
(αht/¯h)˜ct= (1 − θ)˜yt/(htet), 1 = β
γt
˜ ct
˜
ct+1(1 + (1 − τ )(rt+1− δ)) ,
˜
ct+ γtnt˜kt+1− (1 − δ)˜kt= (1 − ψt)˜yt,
˜
yt= ˜kθt(htet)1−θ, rt= θ˜yt/˜kt.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 22 / 26
Calibration
The model is calibrated using the data during 1984-89 (which is found in columns FX-GB in FED_data.xls).
θ = 0.362: average of the capital income share in GNP.
δ = 0.089: ratio of depreciation to the beginning-of-the-year capital stock. τ = 0.480: average of the capital tax.
β = 0.976: obtained from the Euler equation ct+1
ct = β (1 + (1 − τ )(θyt+1/kt+1− δ)) . α = 1.373: obtained from the wage equation so that h(zt) = ¯h (?)
αct= (1 − θ)yt/et= wtht.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 23 / 26
Simulation
The exogenous variables are (At, Nt, ψt) where ψt= Gt/Yt. For the 1990s (t = 1990, 1991, ..., 2000), actual values are used. For t = 2001, 2002, ...,
The growth rate of A1/(1−θ)t is set to its 1991-2000 average of 0.29%. Ntis 2000 value; no population growth.
ψtis set to 1999-2000 value of 15%.
Deterministic simulation is done. The decline of TFP growth in the 1990s is forecasted in 1990.
Also, in our Dynare simulation, we set h(zt) = ¯h = 40 for all t.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 24 / 26
Figure 6-8 in the paper
1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 80
100
120 Detrended y
1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 1.5
2 2.5
Capital-output ratio
1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 0.02
0.04 0.06
0.08 After-tax rate of return
actual HP Dynare
Some comments
Detrended output is close to the model predictions.
Capital-output ratio rises and the rate of return falls as output growth falls, which is seen in the Euler equation.
The model’s prediction is sensitive to the exogenous variables in the 1990s. The most important variable is TFP.
Dynare simulation yields almost the same result as in HP.
T. Sunakawa Hayashi and Prescott (2002) Advanced Macro 26 / 26