The Great Housing Boom in China
Kaiji Chen
y
Yi Wen
z
February 16, 2014
Abstract
China’s decade-long housing boom looks nothing short of a gigantic bubble famil-
iar to many countries: In big cities the price-to-income ratio reached 30 to 1 and the
vacancy rate stood at 30% or above. This paper provides a theoretical framework to
shed light on the causes and consequences of the great housing boom in China. We
argue that the boom could be a rational bubble rooted in China’s unprecedented eco-
nomic transition— which features persistent high returns to capital. We argue that the
very expectation that China’s high capital returns driven by cheap labor and resource
relocations are not sustainable in the long run can induce investors to seek alternative
store of value for their growing wealth, thus triggering a self-ful…lling housing bubble in
a nancially underdeveloped economy with limited supply of nancial assets. The bub-
ble would exhibit a rapidly rising housing price-to-disposable income ratio during the
transition path regardless of whether housing provides rents or utilities. This predic-
tion is consistent with China’s ghost town”phenomenon and decade-long faster-than-
income-growth housing bubble, which cannot be explained by standard neoclassical
growth theory. We show the bubble could prolong China’s economic transition and
severely reduce social welfare. Our model also sheds considerable light on similar hous-
ing bubbles existed in other emerging economies during their rapid economic growth
and transition periods.
Keywords: Housing Bubble, Capital Misallocation, Crowding-Out, Chinese Econ-
omy, Economic Transition.
JEL Codes: E22, E23, O16, O53, P23, P24, P31.
We thank Xiangyu Gong, Xin Wang and Tong Xu for capable research assistance and Jing Wu for
sharing data on China’s housing prices.
y
Economics Department, Emory University.
z
School of Economics and Management, Tsinghua University; and Research Department, Federal Reserve
Bank of St. Louis.
1
1 Introduction
Standard neoclassical theory suggests that housing (land) prices can grow at most as fast
as aggregate productivity under a xed land supply. But this is not true in China. Housing
prices in China experienced rapid and steady accelerations far above productivity growth
since the housing reform in the late 1990s and, especially, in the recent decade. In many
cities, the growth of housing prices signi…cantly outpaced the growth of disposable income.
For example, data based on 35 major Chinese cities show that in most of these cities the
growth rate for real housing prices b etween 2006-2010 are between 15% to 30% per year, far
exceeding the 10% growth rate for real disposable income in these cities.
1
As a consequence,
the nation-wide average house price-to-income ratio increased from around 8 in 1999 to 13
in 2010, and this ratio reached about 30 in big cities such as Beijing and Shanghai, despite
unprecedented income growth. The increase in housing prices is also accompanied by rapidly
rising land values in China. Using data from the local land auction market in Beijing, Wu,
Gyourko, and Deng (2010) show that real constant quality land values have increased by
nearly 800% since the rst quarter of 2003.
Because of the phenomenal rate of return in the housing market, real estate has become
a vital investment opportunity for households, state-owned enterprises, private rms, as well
as commercial banks. So housing investors in China include people from all walks of life,
regardless of their income level and profession, and enterprises of all types, regardless of
their sizes and ownerships. In fact, capital gains from housing investment have become an
important (or even the only) source of prots for many state-owned and private rms. Given
the sheer size of Chinas housing market (with a population of 1.3 billion and 230 millions
new migrants into cities in recent decade and a similar-size migration in the next decade)
and the long duration of the rapid housing-price growth, what we are witnessing can be truly
called one of the greatest housing booms in human history.
The astonishingly high price-to-income ratio seems to suggest excess demand in the
housing market; yet ghost towns”and massive empty apartments across big cities in China
appear to indicate excess supply. As if this mismatch in demand and supply is not puzzling
enough, there exists even a bigger puzzle: housing prices keep growing rapidly in recent years
despite the alarmingly high vacancy ratio.
1
See Wu, Deng, and Liu (2012, Fi g. 5).
2
On the one hand, the great housing boom appears no di¤erent from a typical housing
bubble experienced by many countries, such as Japan in the 1970s and 80s and the United
States in the 2000s, except that the Chinese situation looks worse: The housing price-to-
income ratio in big Chinese cities is twice as high as in Japan when Japan’s housing bubble
burst in 1990, and six times as high as in the United States at the peak of the U.S. housing
bubble in 2005-2006. Vacancy rates in China are between 25% and 30%, well above the
normal range of 5 to 10 percent in advanced countries. On the other hand, the great housing
boom also looks unique to China: the ghost towns, ghost malls, and ghost apartments in
China make even the unprecedented Japanese bubble thirty years ago look pale.
Not surprisingly, the great housing boom in China has generated global attentions. The
fear is that the rapid housing price growth is not sustainable and a collapse of the Chinese
housing market may intensify the current world slump and signi…cantly prolong the world-
wide recession amidst of the world nancial and debt crisis, given China’s increasing role as
an engine of global economic growth. The great housing boom has also caused great concerns
by the Chinese government, as excessive investment in housing can crowd out investment
in xed capital and other real economic activities, and a sudden collapse of the bubble may
cause massive bank failures and jeopardize China’s economic growth potentials.
What economic forces are at work to generate the great housing boom in China? Are
the faster-than-income-growth housing boom sustainable? What are the economic costs of
the great housing boom?
Many conventional views exist to explain the great housing boom in China. One theory
views the boom as a natural consequence of Chinas rapid income growth and rising urban
demand for housing. When total income grows rapidly but the supply of land is inelastic,
a growing demand for housing can easily push up housing prices. This theory predicts that
housing prices can grow as fast as aggregate income growth. Another view is that the housing
boom is a pure bubble because in nancially underdeveloped economies houses can serve as
an attractive store of value even if they provide no utilities (as in the classical Samuelson
model of at money). This view can explain the ghost-town phenomenon in China but
requires the additional assumption that the rate of return to capital (or interest rate) in
China is excessively low so that capital is not an idea asset to invest compared to housing.
But the rate of return to capital in China is not low: Its real rate of return has been above
20% per year over the past decades despite decades-long excessive investment (Bai, Hsieh
and Qian, 2006). Therefore, these conventional views cannot explain why the growth rate
of housing prices in China have remained so high for so long, far exceeding the growth rate
3
of aggregate disposable income despite the excessively high rate of return to capital.
2
This paper provides a theoretical framework to address these puzzles. We show that
the great housing boom in China can be a rational bubble arising naturally from Chinas
unprecedented economic transition which features phenomenal rates of return to capital
driven largely by newly emerging private rms and massive relocations of cheap labor from
rural to urban areas, from po or to rich cities, and from SOEs (state-owned enterprises) to
private enterprises during the transition.
As unprecedented as it is, however, no rational investors would expect China’s growth
miracle to continue forever. The cheap labor resource may one day be exhausted; the high
return to capital may eventually come to an end; and the cheap credit supply due to nancial
repression cannot possibly last forever. In deed, a recent survey of the biggest private rms
in China shows that the top concerns for their future pro…tability are the rising costs in (i)
raw materials, (ii) labor, (iii) credit, and (iv) tax burdens. Thus, the rational anticipation of
increasing costs and declining capital returns in the future would motivate rational investors
to seek alternative stores of value beside capital.
Part of China’s rapid growth came from the government’s massive investment in in-
frastructures. As a result, China’s public debt has increased rapidly over the past decade.
The burden of repaying the debt will ultimately fall upon future generations. This antic-
ipation of rising corporate taxes further reinforces the public’s expectation of low future
after-tax capital returns in the private sector, further encouraging people to seek alternative
stores of value for their growing wealth.
3
Capital controls and an underdeveloped nancial market in China (as is the case for many
developing countries) have limited the availability of stores of value for the rapidly increasing
wealth held by households and entrepreneurs; thus, investing in housing becomes one of the
best choices in China for capital gains.
4
We show that this expectation-drive strong demand
for housing as an alternative store of value, based on the foresight that Chinas low-cost
and high-capital-return economy will eventually come to an end, can generate a large, fast-
growing, and self-ful…lling housing bubble at the present. That is, even if housing provides
no rents or utilities, rational agents would still hold it as a store of value if its rate of return
2
There is another puzzle the standard neoclassical model cannot explain: consumption-to-income ratio in
China has been declining over the past decades (see Wen, 2012). If housing provides utilities and its prices
grow faster than income, then as a normal good the consumption-to-income ratio should also increase over
time.
3
In China government tax income comes mainly from corporate taxes, instead of household income,
because of limited capacity in income-tax collection.
4
Laws in China prohibit people purchasing land as a store of value. Otherwise it may be more cient
to use land rather than vacant houses as a store of value.
4
(capital gain) equals or exceeds that of capital— which is exceptionally high during transition
but would surely be signi…cantly reduced after the transition ends. Consequently, a bubbly
equilibrium exists in which the growth rate of housing prices equals the rate of return to
capital. Hence, along the transition path we will observe a S-shaped housing price-to-income
ratio— with housing price growing much faster than disposable income in the initial stage of
the transition but eventually converging to the growth rate of disposable income in the long
run. This prediction appears consistent with the Chinese data.
We show that the housing bubble could greatly prolong China’s economic transition and
reduce social welfare. Unlike some existing bubble models, in our model housing bubbles
can exist without dynamic ine¢ ciency, due to the disparity between so cial and private rate
of returns to capital. Hence, by crowding out private capital formation and other productive
activities, it creates a negative externality and reduces the permanent income of all agents.
Accordingly, the occurrence of the housing bubble generates a substantial degree of resource
misallocation and welfare losses, prolonging economic transition and slowing down aggregate
economic growth.
Our model not only rationalizes the great housing boom in China, but also shed consid-
erable light on housing bubbles experienced in many emerging economies, such as the Asian
four tigers. These economies all exp erienced a transition period featuring low wage growth
and high capital returns sustained by labor relocations, and also su¤ered from underdevel-
oped nancial markets and the lack of store of value for their growing wealth. Hence, with
currently high capital returns and anticipated low future capital returns, people opt to seek
alternative stores of value for their rapidly accumulated wealth. Given the capital control
policies widely adopted by governments to prevent capital out‡ows, land and housing stocks
become the natural choice of asset investment.
Our paper is related to several strands of the literature. First, our theory relies on a
similar mechanism as in Song, Storesletten and Zillibotti (2011, SSZ”hereafter) to generate
a persistently high rate of return to capital along transition. Speci…cally, SSZ provide an over
lapping generations model with two sectors: one operates with ine¢ cient technology and the
other has superior technology but little access to bank capital, thus must rely on self nance.
They show that labor relocation from the former to the latter sector can generate endogenous
productivity growth at the aggregate level, and account for China’s high income growth, high
capital returns, and large capital account surplus. In SSZ, however, investors’only portfolio
choice is between capital investment and bank deposit. As a result, their paper is silent on
why housing bubbles may occur in China, and thus unable to explain why the allocative
5
ciency in China can become worse as a result of the housing bubble— a phenomenon also
shared by other emerging economies in Asia. By introducing housing as a bubble asset into
the SSZ model, our paper not only sheds light on the formation of housing bubbles along
the economic transition, but also their social costs in terms of resource misallocation and
welfare. In particular, we explain why entrepreneurs in China have strong incentives to
own empty apartments that generate zero rents or utilities. By showing housing bubble as
a natural consequence of economic transition and studying what policies may correct the
consequent distortions, our paper complements SSZ in understanding the typical growth
pattern of emerging economies like China.
Our paper also contributes to the emerging literature on Chinas housing price puzzle.
Most works in this area focus on why the housing price level is so high in China. For
example, Wei, Zhang and Liu (2011) provide a theory to link the high housing price level
in major cities of China to these areas’high household saving rates due to unbalanced sex-
ratio. In sharp contrast, the focus of our paper is on why housing prices in China have
grown faster than aggregate income over the last decade. To understand China’s growing
housing bubble, models that only explain high housing price level from the demand side are
not su¢ cient. More importantly, by shifting the analysis from housing price level to housing
price growth, our paper sheds light on why the rapid growth of housing prices may create
resource misallocation and prolong China’s economic transition, an issue silent in Wei et. al
(2011).
Our paper ts into the fast-growing literature of economic development and resource
misallocation, with a focus on nancial under-development.
5
We share the similar view that
nancial under-development, especially nancial repression, is key to resource misallocation
along transition. To our knowledge, we are the rst to incorporate housing as a bubble
asset in this literature and analyze in detail its social and welfare costs in terms of economic
transition.
Finally, our theory is related to the existing theories on housing bubble. Tirole (1985)
and Farhi and Tirole (2011) emphasize the crowding-out ects of bubble assets on capital
accumulation and its negative welfare ects. On the other hand, Ventura (2012), Martin
and Ventura (2012), Caballero and Krishnamurthy (2006), and Kocherlakota (2009) show
that bubbles can crowd in capital accumulation when rms are b orrowing constrained and
can use the bubble as collateral or a store of value to facilitate intertemporal consumption
smoothing. We show that even if the bubble asset can serve as collateral for borrowing, it
5
See, for example, Buera and Shin (2011) and Moll (2011).
6
can still crowd out capital formation and hinder welfare.
The remaining part of the paper is organized as follows: In Section 2, we present the
empirical facts about China’s growing housing bubble. Section 3 describes a simple 2-period
benchmark model to illustrate our essential ndings. Section 4 reports the model’s simulation
results. In Section 5, we conduct a quantitative analysis based on a multi-period version of
our model. Section 6 concludes.
2 Empirical Facts
2.1 Chronology
China economic reform started in 1978. In the era of planned economy (b etween 1950 and
1978), all housing (apartments) in the city were provided by the government at subsidized
rents. All institutions, no matter whether they are hospitals, schools, or rms, are obligated
to provide housing to their workers. This situation changed gradually since the reform.
In particular, from 1982 to 1985, more than 1,600 cities in China launched pilot projects of
housing reforms. Most of these projects focused on privatizing the existing public apartments
and let residents to pay the market-determined rents. However, due to the delay of wage
reforms and the lack of a nancial system to provide loans, the rst round housing reform
failed.
In 1991, the city of Shanghai built a system of publicly pooled funds for housing nance.
This experiment was later introduced to the entire country between 1994 and 1997. The
pooled funds provided loans to enterprises and public institutions to build private housing
units and to individuals to purchase housing units which was also the only channel for
individuals to obtain loans in those days. During this period, about 20% to 30% of the
existing housing stock was traded in the market, so the bulk of housing units was still
provided by the government at subsidized rates.
Things changed dramatically in 1998, in which year China’s State Council lunched a new
round of housing reform and issued Notice on the Further Deepening of Urban Housing
Reform”(the 23rd Decree). After that, public housing provision essentially ended nationwide
and bank mortgage loans became available to home builders and home buyers in addition
to publicly pooled funds. Consequently, China entered an era of housing market boom. The
share of private housing units in total housing units increases from 30% to more than 70%
between 1998 and 2010.
7
2.2 Housing Prices and Disposable Income
The National Bureau of Statistics of China (NBSC) provides two major housing price indexes.
Based on these housing price indexes, the average growth rate of housing prices in China
is below the average growth rate of household disposable income. However, Wu, Deng,
and Liu (WDL 2012) argue that these measures are severely biased downward because they
include all existing houses in areas that are not yet included by market transactions or do not
have realistic market values. These authors instead use independently constructed housing
price index based on newly-built housing sales in 35 major Chinese cities. Their price index
demonstrates that the government-published data are severely downward biased and fail to
capture the dramatic increases in housing prices across the nation. Based on their data
set on newly-built housing sales, the average housing prices in China’s 35 major cities have
increased from a level of 100 in early 2004 to a level of 250 in late 2009, implying an average
annual growth rate of 17% per year. If we ignore the negative impact of the nancial crisis,
the average growth rate was 20% p er year between 2004 and 2008 and this growth rate
become 25% in the year 2009 (see Panel A of Figure 1). In big cities the growth rate is even
higher. For example, in Shanghai and Beijing the average real growth rate of housing prices
during the same period is 2-3 times higher than the average real growth rate of disposable
income (see Figure 1B).
Yang, Chen, and Monarch (YCM 2010) show that during the post-reform period between
1978 and 2007, Chinas average nationwide real wage growth is only about 6.5% per year.
Wage growth was particularly low (about 4%-5% per year) for the rst sub-period of 1978-
1998. But since the fully-edged housing reform and the SOE reform in 1998, the growth
rate of real wage accelerated to about 10% p er year (8.5% per year in the manufacturing
sector) in the second sub-period in 1998-2007, roughly caught up with the average national
income growth rate in China (see, e.g., Figure 1 in YCM, 2010). So the gap between real
housing price growth and real wage growth in the post housing reform period is at least
7 percentage points. This implies that an initial price-to-income ratio of 8 in 1999 would
become 20 in 2013, consistent with the information reported in the opening paragraph in
the Introduction and the facts presented in Panel B of Figure 1.
6
6
Economic growth in China is highly uneven, including wage income. YCM (2010) also documents that
in some sectors the growth rate of real wage is nearly as high as or even above the average growth rate of
housing prices. This inequality in income growth also suggests that high- and upper middle income classes
in China are fully capable of opting to use housing as their preferred store of value despite the high average
price-to-income ratio. Basically, with a rising average housing price-to-income ratio, although the average
household in China becomes increasingly di¢ cult to use housing as a store of value even if they want to, this
is not true for rich and upper middle income households since their income levels are able to keep pace with
8
2004 2005 2006 2007 2008 2009 2010
100
120
140
160
180
200
220
Housing Price Index, 2004M1=100
Panel A: Housing Price Index
0 2 4 6 8 10 12
0
5
10
15
20
25
30
35
growth rate for rea l p er-cap ita dispo sab le in co m e, %
growth rate for real hedonic housing Price, %
Beijing
Fuzhou
Haikou
Shanghai
Xiamen
Chongqing
Guangzhou
Nanjing
Wulumuqi
Shenzhen
Ningbo
Hangzhou
Qingdao
Changsha
Zhengzhou
Guiyang
Lanzhou
T ianjin
Xining
Taiyuan
Nanchang
Shijiazhuang
Jinan
Chengdu
Hefei
ShenyangHuhehaote
Wuhan
Yinchuan
Nanning
Dalian
Kum ing
Haerbin
Xian
Changsha
P an el B : Hou sin g P rice & Inco m e G rowth
2004 2005 2006 2007 2008 2009 2010 2011 2012 2013
50
100
150
200
250
300
350
400
Hedonic Land Price, 2004q1=100
Panel C: Land Price Index
1998 2000 2002 2004 2006 2008 2010 2012
0
5
10
15
20
25
30
35
year
Marginal Product of Capital
P an el D: Ra te o f Retu rns to P hysica l C apita l
Baseline
Excluding Urban Housing
Figure 1: Housing Prices in China
The increase in housing prices is also accompanied by rapidly rising land values in China
(Panel C of Figure 1). Using data from the local land auction market in Beijing, Wu,
Gyourko, and Deng (2010) show that real constant quality land values have increased by
nearly 800% since the rst quarter of 2003. Among the market participants of land purchases,
state-owned enterprises have played an important role and they in general paid 27% more
than other bidders for an otherwise equivalent land parcel. A rapidly rising land value
bene…ts the land owners (the government in China) but hurts rms, retailers, and consumers
in terms of ce building and rental costs.
Based on data from China Statistical Yearbook 2012, the real estate sector has experi-
enced a spectacular boom since the full-‡edged housing reform in 1998. The share of total
real-estate investment in GDP increased by more than three folds, from 4.2% in 1999 to
13.2% in 2011. In particular, a booming residential investment accounts for about 70% of
the real estate boom: its share in GDP rose from 2.4% in 1999 to 9.5% in 2011, a 4-fold
the housing price growth.
9
expansion— the average nominal growth rate of residential investment is 25.5% per year and
the average nominal growth rate of GDP is 14% per year, so residential investment growth
is more than 11 percentage points above the growth rate of Chinas nominal GDP. These
statistics reinforce the previous housing price data on China’s great housing boom.
Accompanying the fast housing price growth in China is the persistently high rate of
returns to capital. Panel D of Figure 1 shows that the rate of return to capital is on average
20% between 1998 and 2012. In particular, it increases steadily from 18 p ercent in 2001 to
26 percent before the global nancial crisis hit in 2008.
2.3 The Crowding-Out ects on Capital Investment
The rapidly growing housing bubble in China has been crowding out investment and capital
formation of both SOEs and private rms. We measure the crowding-out ects by esti-
mating the correlation coe¢ cients between housing price growth and investment growth. To
remove seasonal ects, all the growth rates are on year-to-year basis, which means growth
rate comparing with the same month in last year. Table 1 presents the correlation between
real housing price growth (deated by Consumer Price Index) and real investment growth
(deated by PPI). Column 2 and 3 show the results based on housing prices at the national
level. The nationwide housing price index may not fully represent the extent of the housing
bubble in China, because of the highly unbalanced growth and inequality across regions.
Therefore, column 4 and 5 show the results based on housing price index at major city level.
Besides reporting the correlation between the investment and housing price growth in cur-
rent period, we also lagged the housing price growth by 1 to 6 months to see how current
housing price growth predicts future investment growth.
From Table 1, we can see that growth of investment on real estate sector is signi…cantly
positively correlated with housing price growth, while investment on other sector is sig-
ni…cantly negatively correlated with housing price growth. More importantly, the results
show that current housing price increases are a strong predictor of future drop in investment
growth, with the peak correlation between housing price growth and investment growth
reached at a lead of 5 month. Such a result is consistent with our model described in the
next section. Column 4 and 5 suggest that if we use housing price index from cities where
the housing prices have experienced sharper increases, we obtain even stronger negative cor-
relation between housing price growth and investment growth, both contemporaneously and
across periods.
10
Table 1. Correlation: Housing Price Growth & Fixed Investment Growth
Nationwide Major Cities
Real Estate Inv. Other Inv. Real Estate Inv. Other Inv.
Current 0.5255
-0.3212
0.4532
-0.5470
t 1 0.4765
-0.4046
0.3725
-0.6567
t 2 0.4115
-0.4499
0.2394 -0.7331
t 3 0.3320
-0.5025
0.1363 -0.7875
t 4 0.2710
-0.5467
0.0666 -0.8011
t 5 0.2025 -0.5438
-0.0830 -0.7750
t 6 0.1288 -0.5171
-0.2195 -0.7009
Signi…cant at 5%.
2.4 Other Facts Concerning the Key Assumptions in Our Model
Timing of Housing Reform and SOE Reform. Under China’s planned economy, SOEs were
the major employers in the cities and they played the pivotal role of maintaining low unem-
ployment and ensuring social stability. SOEs are required to provide all social and pension
bene…ts to employees, the SOE sector had not only low productivity and limited pro…ts,
but also high debt burdens. Naturally, SOEs su¤ered severe losses during the initial reform
period, especially for the small and medium sized SOEs. By the mid-1990s, the Chinese
Government realized that their gradualist reform policy could no longer manage the mount-
ing losses of SOEs and decided to take more aggressive steps, rst allowing the privatization
of small and medium SOE and then, beginning in 1997, moving forward with more aggres-
sive restructuring, accomplished through large scale housing privatization and shifting the
federal responsibility of health insurance, unemployment insurance and pension provisions
to local governments, employers and employees themselves (see YCM, 2010). Therefore,
Chinas housing reform started roughly at the same time and moved in pace with its reform
on the SOE sector. For this reason, we treat housing reform and SOE reform as simultaneous
events in our model. Namely, b efore the housing reform, there were no market for houses and
SOEs are the only enterprises. Workers deposit their savings into the state-owned banking
system, which is channeled into SOEs for capital allocation. After the reform, house becomes
a market commodity. Although it provides no utilities, it can be held as a store of value. At
the same time, the private sector emerges, which relies on own savings to accumulate capital
and compete with the SOEs for labor resources.
Financial Repression and Interest Rate Control. China has made signi…cant progress
since 1978 in opening its economy to the outside world, but nancial reform signi…cantly
lags its economic reform in goods-producing sectors. Chinas nancial repression is easy to
11
see in Figure 2 where interest rates are essentially at with the deposit rate lying substantially
below the lending rate. Funds are channeled through state-owned banks to the conventional
sector mainly occupied by state-owned enterprises (SOEs). There are few investment alter-
natives for household savings, stock markets are poorly regulated and dominated by SOEs,
interest rates are set by government, the capital account is closed, and the exchange rate
is xed or tightly managed. Through a system of strict capital controls where the state
directly manages the banking sector and nancial intermediation, the government has been
able to maintain or suppress interest rates at below market-clearing levels. A xed and low
interest rate was initially imposed by the government as a development strategy to subsidize
industrialization with cheap capital (see Lin, 2012). A below-market interest rate reects
the government’s goal of achieving a maximum rate of capital accumulation and a high level
of employment in the SOE sector. Also, when the interest rate is xed at a level below the
market-determined rate, SOEs would be able to earn positive pro…ts despite in ciency. The
pro…ts are, however, not redistributed back to the households, they are instead re-invested
to maximize the economy’s capital stock.
Figure 2. Chinas One-Year Nominal Interest Rates (%):
Deposit (solid) and Lending (dash).
3 The Benchmark Model
We extend the SSZ model to incorporate an intrinsically valueless asset housing, and prove
that a faster-than-income growing bubble in housing prices exists even if housing provides
12
no rents or utilities to investors. We emphasize the growing nature of the bubble because
the existing bubble literature often focuses exclusively on static bubbles or bubbles that
grow at the rate of technology. We focus instead on bubbles that can grow faster than the
rate of productivity growth. In particular, we show how the very expectations that the
excessively high rate of return to capital during transition is not sustainable in the long
run— can generate a self-ful…lling housing bubble that grows faster than aggregate income
along the transition path.
3.1 The Environment
The economy is populated by overlapping generations of two-period lived agents.
7
Agents
work when young and consume the return from their savings when old. Agents have hetero-
geneous skills. Within each cohort, a measure N
t
=2 of agents have no entrepreneurial skills.
They choose to become workers and supply labor to rms. And the rest of the agents have
entrepreneurial skills so they choose to become entrepreneurs. Entrepreneur skills can be
transmitted from parents to children. The population N
t
grows at an exogenous rate :
Before the economy starts, the government owns one unit of housing (land), which is in
xed supply. At the beginning of the rst period, the government sells it to the market and
consumes all the proceeds.
3.2 Technology
There are two production sectors and thus two types of rms. Labor is perfectly mobile
across the two sectors, but capital is not. The rst sector is composed of conventional
rms F-…rms, which for simplicity are owned by a national bank and operated as standard
neoclassical rms. Workers can work in either sector but deposit their savings into the
national bank. The bank lends capital to F-…rms to produce output.
The second sector is an unconventional or emerging sector, which is composed of high-
productivity rms— E-…rms. The E-…rms are operated by entrepreneurs with over-lapping
generations. More specically, E-…rms are owned by old entrepreneurs, who are residual
claimants on pro…ts and hire their own children as managers. E-…rms have higher total
factor productivity (TFP) than F-…rms. However, E-…rms cannot rent capital from the na-
tional bank.
8
As a result, they must self-…nance capital investment through own savings. By
7
We rst use a 2-period model to illustrate our main results and then extend it to a 50-period model later
on to conduct calibrated quantitative analysis.
8
We will relax this assumption in a later section.
13
contrast, F-…rms can rend capital from the national bank at a xed interest rate R. Accord-
ingly, along transition, an F-…rm can still survive despite with less productive technology.
Over time, however, labor is gradually reallocated from F-…rms to E-…rms as E-…rm sector
capital stock expands.
The technologies of the two types of rms follow constant returns to scale
y
F t
= (k
F t
)
(A
t
n
F t
)
1
;
y
Et
= (k
Et
)
(A
t
n
Et
)
1
;
where y, k, and n denote output, capital stock and labor, respectively. > 1 re‡ects the
assumption that E-…rms are more productive than F-…rms. Technological growth is constant
and exogenously given by A
t+1
= A
t
(1 + z) :
3.2.1 The Workers Problem
Workers can deposit their savings into the bank and earn a xed interest rate R. But for
simplicity and without loss of generality, we assume that workers cannot speculate in the
housing market.
9
The worker’s consumption-saving problem is
max
c
w
1t
;c
w
2t+1
log c
w
1t
+ log c
w
2t+1
subject to
c
w
1t
+ s
w
t
= w
t
c
w
2t+1
= s
w
t
R
where w
t
is the market wage rate, c
w
1t
; c
w
2t+1
and s
w
t
denote respectively the consumption when
young and old, and the workers savings.
t+1
is a lump-sum transfer from the bank (to be
speci…ed below). The rst order conditions imply
s
w
t
=
1
1 +
1
w
t
Namely, the optimal level of saving is proportional to the income received when young.
9
In an appendix upon request, we show that allowing workers to invest in housing does not change our
results— the dynamics of housing price is una¤ected.
14
3.2.2 The F -Firms Problem
In each period, F-…rms maximize pro…ts by solving the following problem
max
k
F t
;n
F t
(k
F t
)
(A
t
n
F t
)
1
w
t
n
F t
Rk
F t
;
where the rental rate for capital is the same as the deposit rate, R: The rst-order conditions
are
w
t
= (1 ) k
F t
A
1
t
n
F t
R = k
1
F t
A
1
t
n
1
F t
(1)
This gives
w
t
= (1 ) A
t
R
1
(1 ) A
t
F
(2)
where
F
k
F t
A
t
n
F t
=
R
1
1
: Note that along transition, the (detrended) wage rate,
w
t
A
t
, is
constant, due to a constant rental rate for capital. When the transition ends, all F-…rms
disappear, so equation (2) no longer holds.
3.2.3 The E-Firm’s Production
Following SSZ, we assume that young entrepreneurs get paid a management fee m
t
that is
a xed < 1 fraction of the output produced.
10
Therefore, the old entrepreneur’s problem
can be written as
max
n
Et
(1 ) (k
Et
)
(A
t
n
Et
)
1
w
t
n
Et
The rst-order conditions imply
(1 ) (1 ) (k
Et
=n
Et
)
(A
t
)
1
= w
t
= (1 ) A
t
R
1
; (3)
where the second inequality comes from (2) based on the assumption of perfect labor mobility
across rms. Equation (3) immediately implies a linear relationship between n
Et
and k
Et
n
Et
= [(1 ) ]
1
R
1
1
k
Et
A
t
: (4)
10
SSZ provides a microfoundation for young entrepreneur’s management fee as a xed fraction of output:
There exists an agency problem between the manager and owner of the business. The manager can divert
a positive share of the rm’s output for his own use. Such opp ortunistic behavior can only be deterred by
paying managers a compensation that is at least as large as the funds they could steal, which is a share
of output.
15
Such a linear relationship is obtained because of the constant interest rate R; which implies
a constant wage rate: Accordingly, labor is reallocated to E-…rms at a speed equal to the
growth of the private capital stock in the E-rm sector. The pro…t of the E-…rm is
(k
Et
) = (1 ) (k
Et
)
(A
t
n
Et
)
1
w
t
n
Et
= (1 )
1
1
Rk
Et
E
k
Et
;
where the second equality is obtained by using (4). Whenever F-rms exist, the return
to capital in E-…rms,
E
[(1 )]
1
1
R, is a constant. This is because n
Et
increases
linearly in k
Et
: As a result,
E
=
k
Et
:
A
t
n
Et
is a constant during the transition.
3.2.4 The Consumption-Saving Problem of the Young Entrepreneur
The young entrepreneur obtain m
t
= (k
Et
)
(A
t
n
Et
)
1
as income when young, and
decides consumption and portfolio allocation in housing investment, bank deposits, and
physical capital investment. The return for capital investment is simply
E
. By arbitrage,
the return to capital must be equal to or larger than the capital gains from housing:
P
H
t+1
P
H
t
E
: (5)
Hence, a young entrepreneur’s income when old is simply
E
s
Et
, where s
Et
denotes total
savings: Therefore, a young entrepreneur’s consumption-saving problem is
max
s
Et
log (m
t
s
Et
) + log
E
s
Et
The rst-order conditions imply
s
Et
=
1
1 +
1
m
t
:
We assume that a fraction
Et
of s
Et
is invested in rms’capital, and the rest in housing, such
that K
Et+1
=
Et
s
Et
N
t
: Entrepreneurial housing demand is then (1
Et
) s
Et
N
t
= p
H
t
H
Et
.
The optimal portfolio
Et
is pinned down in equilibrium.
16
3.2.5 The Bank’s Problem
For exposition, we assume that each period the bank simply absorbs deposits from young
workers, rent them to F-…rms at interest rate R, and invest the rest in foreign bonds with
the same rate of return.
3.2.6 Time Line
To summarize, in each period the economic events in our model unfold as follows:
1. At the beginning of period t, production of E-…rms and F-rms takes place. The capital
stock used by E-rms is k
Et
, which is from the savings of the entrepreneur when young.
The capital stock used by F-…rms is K
F t
, which is rented from the bank in the last
period (pre-determined in period t 1). Each young worker gets w
t
regardless which
sector they work in. Each young entrepreneur gets m
t
.
2. The young entrepreneur chooses consumption and make saving decision s
Et
. Young
workers make consumption and deposit decisions.
3. Housing market opens. Old entrepreneurs sell housing stock held in the previous period,
H
Et1
; in the housing market, consume, and die. Young entrepreneurs make portfolio
decision
Et
and invest a fraction of wealth (1
Et
) s
Et
in housing, P
H
t
H
Et
.
4. F-…rms repay their rentals to the bank.
5. The currently old workers consume and die. So do the currently old entrepreneurs.
3.2.7 Law of Motion for K
Et
We now derive the law of motion for the capital stock held by E-…rms. Since E-…rm is
self-…nanced, we have
K
Et+1
=
Et
s
Et
N
t
=
Et
1
1 +
1
m
t
N
t
Note that m
t
= (k
Et
)
(A
t
n
Et
)
1
= k
Et
1
E
1
; where
E
k
Et
A
t
n
Et
=
F
[(1 ) ]
1
:
17
Hence
K
Et+1
=
Et
1
E
1
1
1 +
1
k
Et
N
t
=
Et
(
[(1 ) ]
1
R
1
1
)
1
1
1 +
1
K
Et
=
Et
E
(1 )
1
1 +
1
K
Et
=
Et
E
K
Et
(6)
where
E
E
(1 )
1
1+
1
: The second equality follows equation (4) ; whereas the third equa-
tion follows the denition of
E
: Equation (6) shows that the growth rate of private capital
(
K
Et+1
K
Et
) increases with the share of entrepreneurial savings in physical capital,
Et
.
With equations (4) and (6) ; we can derive the law of motion for labor in the E-…rm sector
as
N
Et+1
N
Et
=
K
Et+1
K
Et
(1 + z)
=
Et
E
1 + z
3.3 Post-Transition Equilibrium
We need to characterize the equilibrium after the transition ends, i.e., when n
Et
= 1, k
F t
= 0.
Since n
Et
= 1, the pro…t of the E-rm is
(k
Et
) = (1 ) (k
Et
)
(A
t
)
1
Note that (k
Et
) now features decreasing returns to scale. The average rate of return for
capital investment is simply
t+1
k
Et+1
E
(k
Et+1
) = (1 ) (k
Et+1
)
1
(A
t+1
)
1
: (7)
The law of motion for capital is
K
Et+1
=
Et
1
1 +
1
(K
Et
)
(A
t
N
t
)
1
(8)
18
Finally notice that
P
H
t1
H
Et1
=
1
Et1
s
Et1
N
t1
=
1
Et1
E
t1
(1 )
1
1 +
1
K
Et1
(9)
Note that
E
(
Et
) is a function of
Et
:
3.3.1 Housing Demand and Housing Price
We now determine the housing demand by young entrepreneurs and the equilibrium housing
price. Note rst that the housing demand satises
P
H
t
H
Et
= P
H
t
H:
Consider two cases:
Case 1: R <
P
H
t+1
P
H
t
=
E
To derive the key equation on
Et
; note that
P
H
t
H
Et
= (1
Et
) s
Et
N
t
= (1
Et
)
1
1 +
1
(K
Et
)
(A
t
N
Et
)
1
(10)
Case 2:
P
H
t
P
H
t1
<
E
: In this case, entrepreneurs will not invest in housing, i.e.
Et
= 0.
Then P
H
t
= 0. In this paper, we focus on the equilibrium with housing.
3.4 Characterizing the Equilibrium
Since all per-capita variable (except for n
Et
) grow at the rate A
t
; we detrend all per capita
variables as bx
t
= x
t
=A
t
:
3.4.1 Steady State
At the steady state, we have
E
= (1 )
b
k
E
=
1
= (1 )
1 +
1
(1 + z) (1 + )
E
;
19
where the second equality is derived from (25). With the no-arbitrage condition b etween
housing and physical capital, we have
(1 )
1 +
1
(1 + z) (1 + )
E
=
P
H
t+1
P
H
t
= (1 + z) (1 + )
This gives the share of saving of E-rm in physical capital at the steady state
E
= (1 )
1 +
1
= (11)
Intuitively, the larger is the returns to capital for the entrepreneur, as captured by (1 ) ;
the larger is the share of entrepreneurial savings in physical capital. On the other hand, the
larger is and , which re‡ects a higher income of young entrepreneur and their saving
propensity, the lower is the returns to physical capital and thus the lower would b e the share
of entrepreneurial savings in physical capital.
Note that in our economy, we need
E
< 1 for housing to exist: This implies that without
housing the private return to physical capital by entrepreneurs will b e below the balanced
growth rate. This implies the following parameter restriction
(1 )
1 +
1
< (12)
Intuitively, a larger ects the rate of returns for capital for the old entrepreneur in two
way: rst, it directly reduces the output share accrued to the old entrepreneur; second, by
increasing the output share of the young entrepreneur, it increases the capital accumulated
by the young and thus pushing down the marginal product of capital. In addition, we need
to assume the returns for housing is larger than the bank deposit rate
P
H
t+1
P
H
t
=
E
= (1 + z) (1 + ) > R:
To summarize, we have the following equations at steady state,
b
k
E
=
"
E
1
1 +
1
(1 + z) (1 + )
#
1
1
(13)
E
= (1 )
b
k
E
=
1
(14)
p
H
h = p
H
h
E
(15)
p
H
h
E
= (1
E
)
1
1 +
1
E
1
: (16)
20
3.4.2 Existence and Normative Implications of Bubbles
Di¤erent from the neoclassical growth model, in our economy, the old entrepreneur’s returns
to capital,
E
; is only a fraction, 1 ; of the marginal product of capital for E-…rms, which
is the social rate of returns to capital. This implies that housing bubbles may exist even
under dynamic ciency. The condition for dynamic ciency is that
@y
E
=@k
E
j
E
=1
> (1 + z)(1 + v) (17)
At steady state, with (13) under
E
= 1; (17) implies
< (1 +
1
): (18)
Intuitively, the smaller is, the smaller is the steady-state capital and the higher is its
marginal product. Also, similar to standard OLG models, a higher or a lower make the
economy less likely to be dynamic in cient.
An interesting issue is the normative implication of bubbles in an economy without
dynamic ine¢ ciency. This implication is interesting because bubbles can exist in our model
without dynamic ine¢ ciency, and they reduce the aggregate resource available for aggregate
consumption. In Proposition 1, we show that the following condition is su¢ cient for bubbles
to exist and to crowed out aggregate consumption of the investors:
+ (1 )
< (1 +
1
) (19)
Note that <
+(1 )
: Hence, condition (19) satis…es equation (18), which implies that
the economy is dynamically cient.
A combination of (12) and (19) gives the following parameter restriction
(1 )
1 +
1
< < (1 +
1
) [ + (1 )] (20)
We now derive the normative implication of bubbles under condition (20). De…ning the
aggregate consumption at period t of agent j 2 fw; Eg as bc
j
t
= bc
j
1t
+ bc
j
2t
(1 + v)
1
, we have
the following
Proposition 1 : Given (20), a housing bubble reduces aggregate consumption and welfare—
measured by the lifetime utility of both the workers and the entrepreneurs at the steady state.
21
Proof: see Appendix.
The intuition is clear. When the economy is dynamically cient, a housing bubble will
reduce the aggregate resource available for consumption. If the marginal product of capital
is su¢ ciently high, then choosing housing as an alternative store of value would crowed out
capital and reduce consumption.
Regarding social welfare, since the workers’ wage income decreases with capital stock
but the rate of return to saving (the deposit rate) is xed, their lifetime utility decreases as
a results of housing bubble. For the entrepreneurs, the utility loss due to a fall in lifetime
entrepreneurial income dominates the welfare gain arising from the income ect of a higher
capital return. Hence, both workers and entrepreneurs su¤er welfare losses.
Proposition 2 Given (20), a housing bubble reduces the aggregate consumption of workers
(after the transition ends) and the aggregate consumption of entrepreneurs.
Proof: see Appendix.
Since the wage rate is a constant, it is una¤ected by the presence of a bubble along
the transition. Hence, the welfare of workers along transition is unected by the bubble.
However, when the transition ends, the wage rate changes with the physical capital. So a
bubble reduces the welfare of all workers in the post-transition period.
For entrepreneurs along transition, the rate of return to capital is unected by the
presence of a bubble. Hence, given the initial capital stock, the utility of the old and young
entrepreneurs alive in the rst p eriod are unchanged when a housing bubble is introduced.
From the second perio d on, however, the income of the young entrepreneur will fall due to
the crowding out of capital by the bubble. Hence, all entrepreneurs along transition will
have lower welfare (since the return to capital is constant). For entrepreneurs alive in the
post-transition period, the rate of return to capital is not constant but higher than that at
the steady state. So the loss in income due to a reduction in capital stock is still higher than
the gain from the higher rate of return to capital. Hence, they also su¤er welfare losses as a
result of housing bubble.
3.4.3 The Housing Price to Output Ratio
We now characterize the dynamics of housing price-to-income ratio, one of the key focuses
of the paper. We rst establish a lemma about the dynamics of the share of entrepreneurial
savings in housing.
22
Lemma 3 Throughout the transition and post-transition period, the share of entrepreneurial
savings in physical capital is constant,
Et
=
1 +
1
(1 )
; 8t: (21)
Proof: see Appendix.
To understand the intuition b ehind Lemma 3, we plug the value of
Et
into the law of
motion for capital
K
Et+1
= (1 ) (K
Et
)
(A
t
n
Et
N
t
)
1
(22)
=
E
t
K
Et
:
(22) implies that not only capital accumulated by entrepreneur is linear in current output, but
is a constant fraction of output over time. The higher is the fraction of output attributable
to the old entrepreneurs, as captured by (1 ) ; the larger is the share of current output
going to the end-of-period capital stock. And this constant fraction of output devoted to
capital accumulation is achieved by the portfolio choice of entrepreneurs according to (21) ;
which is constant under constant marginal propensity to save in our two-period model. With
Lemma 3, the following proposition captures the dynamics of housing price to output ratio.
Proposition 4 The housing price-to-output ratio and housing price-to-wage ratio in the
post-transition period are constant, while they are both increasing during the transition.
Proof: We rst prove that the ratio of housing price to aggregate output is constant
in post-transition period. Since the growth rate of housing price is equal to
E
t+1
; this is
equivalent to prove that the growth rate of aggregate output in post-transition period is
equal to
E
t+1
:
Y
t+1
Y
t
=
Y
t+1
K
t+1
K
t+1
Y
t
=
E
t+1
(1 )
(1 ) =
E
t+1
;
where the second equality is obtained by the de…nition of
E
t+1
and (22) : Therefore, the
housing price to output ratio is constant in post-transition period. Since wage is a constant
fraction (1 ) (1 ) of aggregate output, it is straight forward that the housing price-
wage ratio is constant in post-transition period.
23
Along the transition stage, we have
Y
t+1
Y
t
=
Y
F t+1
+Y
Et+1
Y
F t
+Y
Et
: Equation (1) implies that the
growth rate of output by F-…rms follows
Y
F t+1
Y
F t
=
RK
F t+1
=
RK
F t
=
=
K
F t+1
K
F t
< 0
Therefore, we have
Y
t+1
Y
t
<
Y
Et+1
Y
Et
=
E
t+1
=
P
H
t+1
P
H
t
;
where the proof of the second equality follows the same procedure as that for the post-
transition perio d. As a result, the housing price to output ratio will increase along the
transition.
The intuition of Proposition 4 is as follows. In the post-transition period, the economy
essentially becomes a neoclassical economy. In our simple model with full capital deprecia-
tion, the end-of-period physical capital is proportional to the current aggregate output, with
the share equal to the next-period share of output going to old entrepreneur. Hence, the
housing price to output ratio is constant during the post-transition period. Note that this
property also holds in a neoclassical framework (with complete capital depreciation).
During the transition, however, the aggregate output growth is an average of the output
growth of the E-…rms and F-…rms. Since F-…rms keep downsizing due to labor reallocation,
the aggregate output growth is less than the output growth rate of the E-…rms, which equals
to the returns to capital for the old entrepreneur. Therefore, the housing price will grow
faster than the aggregate output (and wage rate, which is constant) along transition.
3.5 Numerical Algorithm
During transition, we have the following equation to determine labor allocated to E-rms:
n
Et
= [(1 ) ]
1
R
1
1
k
Et
A
t
= [(1 ) ]
1
R
1
1
b
k
Et
=
We check if n
Et
> 1: If so, we set n
Et
= 1:
24
Also, we have the following equations for both transitional and post-transitional periods
bw
t
= (1 ) (1 )
b
k
Et
=n
Et
1
(23)
t
= (1 )
1
[(1 ) = bw
t
]
1
1
(24)
b
k
Et+1
=
Et
b
k
Et
(n
Et
)
1
=
(1 + ) (1 + z)
1 +
1

(25)
bp
H
t
=
bp
H
t+1
(1 + z) (1 + ) =
t+1
if
Et
< 1
0 if
Et
= 1
(26)
bp
H
t
h
Et
= bp
H
t
h (27)
bp
H
t
h
Et
= (1
Et
)
b
k
Et
(n
Et
)
1
=
1 +
1
We assume the second transition period takes T p eriods. At period T , the economy
enters the steady state. The algorithm to solve for the transition takes the following steps:
1. guess the sequence of f
Et
g
T 1
t=1
:
2. given k
Et
, compute
n
n
Et
; bw
t
;
t
;
b
k
Et+1
; bp
H
t
; h
Et
o
according to the above equations.
3. Check the following condition for each period t = 1; 2; ::; T 1
Et
= 1
1 +
1
bp
H
t
h
Et
b
k
Et
(n
Et
)
1
(28)
and (since
E
T +1
not known)
b
k
E
T +1
=
b
k
E
=
"
E
1
1 +
1
(1 + z) (1 + )
#
1
1
4 Numerical Results
We use the following parameter values for the numerical exercise: = 0:3; = 0:96
30
;
= 0:62 (note > = :5691). = 4:98: R = 1:0147; z = 0:0147; = 0: h = 1; z = 0:0147:
These parameters satisfy the condition (20) to ensure housing bubbles exist in an economy
with dynamic ciency. We also choose k
E1
= 0:031; such that the economy experiences a
transition stage. Note that a smaller k
E1
tends to prolong the transition. But it also makes
25
wage and thus the saving rate of the young worker smaller. At the same time, a smaller k
E1
makes 1 n
Et
and thus k
F 1
larger. This will also tend to make smaller the bank deposit net
of capital demand by F-rms, as well as the housing demand by the banking sector.
4.1 Benchmark Results
Figure 3 shows the dynamics of the benchmark economy. In Panel A, capital in E-…rms
increases at a faster rate during the rst three periods than thereafter. This is because
the marginal product of capital is constant when F-…rms exist, as labor is kept reallocating
from F-…rms to E-…rms. This can be seen in Pane B. At period 4, the transition is over, as
n
Et
= 1. Panel C shows that aggregate output follows a similar growing pattern to that of
physical capital in E-…rms.
Panel D shows the consumption pattern during transition. Notice that during transition,
consumption of E-rms grows fast while that of workers is essentially at due to a constant
wage pro…le. As a result, most of the increase in aggregate consumption is due to the increase
of consumption of entrepreneurs. In Panel E, we see that during transition, the aggregate
rate of returns for capital, which is weighted average rate of returns for capital for E-…rms
and F-…rms is increasing, since the capital share of E-…rms keep increasing. However, during
the post-transition stage, the aggregate returns to capital, which is simply the E-…rm’s rate
of returns to capital, starts to decline. In Panel F, total factor productivity increases along
transition, since resources are reallocated to the E-rm, which is more productive. However,
in the post-transition stage, the (detrended) TFP, which is the productivity of E-…rms, is
constant.
1 2 3 4 5 6
0
0.2
0.4
Panel A: Capital in E Firm
1 2 3 4 5 6
0
0.5
1
Panel B: Labor in E Firm
1 2 3 4 5 6
0.5
1
1.5
2
Panel C: Aggregate Output
1 2 3 4 5 6
0
1
2
period
Panel D: Consumption
1 2 3 4 5 6
1
2
3
4
Panel F: Total Factor Productivity
period
1 2 3 4 5 6
1
1.5
Panel E: Returns to Capital
period
Total
HH
E
26
Figure 3. Macro Variables in the Benchmark Economy.
Figure 4 shows the dynamics of housing prices and share of entrepreneurial savings in
housing. Panel A shows the detrended housing prices growth rate, which track the returns
for capital in E-…rms. Note that the rate of returns for physical capital starts to fall in
period 4, when the transition is over. As a result, the growth rate of housing price is high
along transition, but exhibits a declining pattern in the post-transition period. Eventually,
housing prices in the long run equal the balanced growth rate of the economy. Panel B shows
the ratio of housing price to income. We see that the housing price to wage ratio increases
dramatically. This is because, as Panel C shows, that wage rate is constant along transition
due to the presence of F-…rms and labor reallocation. Similarly, the ratio of housing price
to aggregate output, P
H
t
=Y
t
; keeps increasing during transition, but becomes a constant in
the post-transition stage. Again, this is because during transition, housing prices grows at
a rate faster than the growth rate of the aggregate output, as Proposition 3 argues.
Finally, in Panel D, we see that the share of E-…rms’saving in housing is constant in this
two-period economy. Note that even entrepreneurs along transition demand housing despite
a high rate of returns for capital. This is essentially because those entrepreneurs alive during
transition expect that the high capital returns driven by cheap labor and resource relocations
are not sustainable in the long run, which induces future investors to seek alternative store
of value for their growing wealth. This pushes up the expected rate of returns for housing
even during transition. As a result, entrepreneurs born along transition in our benchmark
economy have incentive to hold housing.
1 2 3 4 5 6
1
1 .5
2
P a ne l A : R e tu rn to K vs. H
rho
K
rho
H
0 2 4 6
0.01
0.012
0.014
0.016
0.018
0.02
0.022
0.024
0.026
0.028
0.03
Price to Output Ratio
Panel B: Housing Price/Income
0 2 4 6
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0 .1
0.11
0.12
Price to Wage Ratio
P /Y
P /W
1 2 3 4 5 6
0.3
0.35
0.4
0.45
0.5
0.55
Panel C: W age Rate
1 2 3 4 5 6
0
0.05
0.1
0.15
0.2
0.25
Panel D: Share of E Firm Savings in Housing
Figure 4. Housing Dynamics in the Benchmark Economy
27
4.2 Counterfactual Experiments
We now explore the key ingredients in our model that help to sustain a high growth rate of
housing price along the transition. To this end, we conduct several counterfactual experi-
ments, in which we shut down one of the ingredients at a time. We examine two ingredients:
(i) the role of the entrepreneurial returns to capital at the steady state, (ii) the role of rm
heterogeneity.
4.2.1 The Role of Bubbles for Transition and Welfare
We would like to explore the role of bubbles for the transition as welfare. Similar to all studies
on bubbles, in our model, the existence of bubbles rely on the assumption that at steady
state, the rate of returns for capital for entrepreneurs is lower than the balanced-growth rate
(though the economy can be dynamic e¢ cient). Therefore, to eliminate housing demand by
entrepreneurs at the steady state, we impose an output subsidy to E-…rms only at the steady
state to equalize the rate of returns to capital for entrepreneurs at the steady state to the
balanced growth rate. We keep all other parameters the same as before.
11
Accordingly, an
E-rm’s problem at steady state becomes
max
n
Et
(1 +
yt
)
(1 ) (k
Et
)
(A
t
n
Et
)
1
w
t
n
Et
Note that the subsidy is proportional to the net prot. Accordingly, the rst-order condition
for n
Et
and the capital-labor ratio is still the same as in our benchmark economy. The pro…t
of the entrepreneur is
(k
Et
) = (1 +
yt
)
E
t
k
Et
Figure 5 plots the transitional dynamics for both the counterfactual and the benchmark
economies. Panel A shows that throughout the transition, housing price is zero. Panel B,
C and D suggest an improvement of allocative ciency in this counterfactual experiment,
as both capital accumulation by E and aggregate output are higher than their counterparts
in the benchmark economy. Moreover, the transition period is shorter, as labor demand by
E-rms has reached 1 in period 3. Panel E and F show that the counterfactual economy
generates higher aggregate consumption, and consumption for both entrepreneurs and work-
ers. Intuitively, more entrepreneurial savings towards capital investment also increase future
entrepreneurs’permanent incomes.
11
We nd that the transitional pattern of this economy, except for the returns to capital, is equivalent to
another economy in which entrepreneurs are shut down from access to housing markets.
28
1 2 3 4 5 6
0
0.05
0.1
Panel A: Housing Price
Bench.
Counter.
1 2 3 4 5 6
0
0.1
0.2
0.3
0.4
Panel B: Capital in E Firm
1 2 3 4 5 6
1
1.5
2
2.5
Panel D: Aggregate Output
1 2 3 4 5 6
0
0.5
1
P a ne l C : L ab or in E Firm
1 2 3 4 5 6
0.5
1
1.5
2
Panel E: A ggregate Consumption
1 2 3 4 5 6
0
0.5
1
1.5
Panel F: Consumption of Different A gents
HH, benc.
HH, counter.
E, bench.
E, counter.
Figure 5: Transition in Economy without Dynamic In ciency
In summary, our experiment shows that housing bubbles crowds out physical capital,
prolongs transition and reduces consumption for both entrepreneurs and workers.
4.2.2 The Role of Firm Heterogeneity
We now examine the second key ingredient of our model: heterogeneous rms in both pro-
ductivity and access to nancial markets. This feature allows the existence of a transition
stage where labor is reallocated from F-…rms to E-…rms. Accordingly, the marginal product
of capital for E-…rms is constant along the transition. We argue that this feature is key to
sustaining the persistently high growth rate of housing prices during transition.
To examine the role of heterogeneous rms, we construct an counterfactual economy
where F-…rms are absent. In other words, all labor is employed in E-…rms at the very
beginning. As a result, all E-…rms are neoclassical in nature except that they are self-
nanced. We still keep the ingredient of dynamic ine¢ ciency in the long run. Therefore,
both the counterfactual and the benchmark economy share the same steady state.
In Panel A of Figure 6, we see that labor demand for E-…rms is always 1. Accordingly, as
entrepreneurs accumulate capital, the return for capital drops quickly from an initially high
level to a very low level at the steady state (Panel B). In Panel C, wage rate starts to increase
at the beginning of the economy. Panel D shows that housing price starts at a higher level,
but overtime the growth of housing prices slows down, in contrast to a fast increase during the
transition stage of the benchmark economy. Accordingly, housing price-to-aggregate output
29
ratio is constant (Panel E). Finally, throughout transition, aggregate consumption is now
higher than the benchmark economy, though they converge to the same steady state. This
implies that the negative ect of housing on aggregate consumption is particularly large in
our benchmark economy. The reason is that in our benchmark economy during transition,
the rate of returns to capital is very high due to labor reallocation. Therefore, the welfare
loss of the crowding-out ect of housing is much larger in our benchmark economy.
12
In summary, the presence of rm heterogeneity (in both technology and access to nancial
markets) helps maintain a high rate of return to capital during the transition. Accordingly,
with entrepreneurial demand for housing, the equilibrium growth rate of housing prices is
high along the transition. Without the presence of F-…rms, the dynamics of housing prices
essentially follows the growth rate of the aggregate output. As a result, the housing price-
to-output ratio is constant without rm heterogeneity. Moreover the welfare loss of the
economy due to housing as bubbles is much larger with rm heterogeneity.
1 2 3 4 5 6
2
4
Panel B: Return to Physical Capital and H
1 2 3 4 5 6
0
0.05
0.1
Panel D: Housing Price
1 2 3 4 5 6
0.4
0.6
Panel C: Wage Rate
1 2 3 4 5 6
0
0.05
Panel E: Housing Price/Aggregate Output
1 2 3 4 5 6
0.2
0.4
0.6
0.8
1
Panel A: Labor in E firm
Bench.
w/o F Firm
1 2 3 4 5 6
0.5
1
1.5
2
Panel F: Aggregate Consumption
Figure 6: Transition in Economy without Firm Heterogeneity
5 Quantitative Analysis
[to be added]
12
Note that in this counterfactual economy, housing still causes welfare loss to workers and entrepreneurs,
since the economy is dynamic cient and satis…es (19) :
30
6 Conclusion
This paper provides an explanation to the great housing bo om in China. In particular, we
show in an endogenous growth model that the great housing bo om can be a rational bubble
arising naturally from China’s unprecedented economic transition, which features persistent
and exceptional high returns to capital— driven largely by massive reallocations of cheap
labor from unproductive sectors to productive sectors. Since the transition will eventually
come to an end, capital returns are expected to decline sharply in the future. Based on
such rational expectations, investors opt to seek alternative stores of value for their growing
wealth. Given Chinas underdeveloped nancial market and capital controls, investors opt
to speculate in the housing market in an early stage by holding the housing stock as a
hedge for their wealth in addition to capital. This generates a strong speculative demand
for housing investment, which recti…es the anticipated housing price boom and leads to a
growing housing bubble with a rate of return equal to that of capital. Consequently, the
economy exhibits an increasing housing price-to-income ratio and an increasing share of
housing investment in GDP during the transition. Such a growing housing bubble crowds
out capital accumulation, prolongs economic transition and reduces welfare for all agents in
the economy.
There are many issues left for future research concerning the ects of housing bubble
in China. For example, housing bubble reduces the private sector’s incentive to innovate.
Because of the relatively low risk, low entry costs, low technology, and high pro…ts in housing
investment, the housing bubble has enticed many productive and high-tech rms in China
to reallocate resources from R&D to the real estate market. In an economy transiting from
labor intensive economy to capital intensive economy, such resource misallocation can be
very costly: It may substantially prolong Chinas economic transition and reduce Chinas
TFP growth, especially when its population is aging fast and labor costs rapidly rising. We
plan to quantify such resource misallocation within our framework in future works.
Furthermore, the rapidly rising housing prices have caused great social concerns as more
and more low-income households are excluded from the housing market— because their in-
come growth falls behind housing price growth. The housing price growth is driven largely
by upper middle income class who has enjoyed the most rapid income growth during the
economic development. The inequality in wealth distribution in China has thus widened and
exacerbated recently, mainly because of the rising housing prices. Again, this is an important
issue for our future research.
31
References
[1] Buera, F. and Y. Shin (2011), Productivity Growth and Capital Flows: The Dynamics
of Reforms”, working paper.
[2] Caballero, R., and A. Krishnamurthy (2006), Bubbles and Capital Flow Volatility:
Causes and Risk Management,”Journal of Monetary Economics, 53(1): 35— 53.
[3] Yongheng Deng, Randall Morck, Jing Wu and Bernard Yeung, Monetary and Fiscal
Stimuli, Ownership Structure, and China’s Housing Market,” NBER working paper
16871.
[4] Farhi, E. and J. Tirole (2012), Bubbly Liquidity,”Review of Economic Studies, 79(2),
678-709
[5] Kocherlakota, N. (2009), Bursting Bubbles: Consequences and Cures,” mimeo, Uni-
versity of Minnesota.
[6] Martin, A. and J. Ventura (2012), Economic Growth with Bubble,” American Eco-
nomic Review, 102(6), 3033-3058.
[7] Moll (2012), Productivity Losses from Financial Frictions: Can Self-…nancing Undo
Capital Misallocation?,”working paper.
[8] Song, Zheng, Kjetil Storesletten and Fabrizio Zillibotti (2011), Growing Like China,”
American Economic Review, 101, 196-233.
[9] Tirole, J. (1985), Asset Bubbles and Overlapping Generations,”Econometrica, 53 (6),
1499-1528.
[10] Ventura, J. (2011), Bubbles and Capital Flows,”Journal of Economic Theory, 147(2),
738-758.
[11] Wu, Jing, Joseph Gyourko, Yongheng Deng (2012), Evaluating Conditions in Major
Chinese Housing Markets," Regional Science and Urban Economics, 42 (3): 531-543.
[12] Yang, Dennis Tao, Vivian Weijia Chen, Ryan Monarch (2010), Rising Wages: Has
China Lost its Global Labor Advantage?”Pacic Economic Review, 15(4), 482-504.
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Prices: Some Evidence from China”, working paper.
32
7 Appendix
7.1 Proof of Propositions
In this section, we prove the various propositions.
Proof of Proposition 1. To prove this proposition, consider a counterfactual economy
without housing, i.e.
E
= 1. According to (13) ; introducing housing (i.e.
E
< 1)
at the steady state would reduce physical capital. Hence, we only need to show under
which condition reducing physical capital at steady state reduces aggregate consumption for
both entrepreneurs and workers. Aggregating the budget constraint of the young and old
entrepreneurs at period t, we get
bc
e
t
= bm
t
+
E
t
b
k
Et
b
k
Et+1
(1 + z)(1 + v) (29)
In our steady state analysis below, we drop the time subscript for notation concision.
Taking the derivative of the right side of (29) with respect to
b
k
Et
at the steady state, we
can obtain the following su¢ cient condition for introducing bubbles to reduce aggregate
consumption for entrepreneurs.
@m=@k
E
+
E
+
E0
b
k
E
b
k
E
> (1 + z)(1 + v) (30)
On the left side of (30) ; @m=@k
E
is the marginal cost on the young entrepreneur’s income
of a reduction in physical capital. The second argument,
E
; refers to the marginal pro…t
loss to the old entrepreneur of a reduction in physical capital. Finally,
E0
b
k
E
b
k
E
is the
marginal benet of reducing capital in terms of an increase in marginal product. The right
side of (30) is the returns for bubbles at the steady state. Using the de…nition of m and
E
;
it is easy to show that (30) can be rewritten as
1
+
E
> (1 + z)(1 + v) (31)
At steady state, with
E
= 1; we obtain the value of
E
by combining (14) and (13)
E
=
1 +
1
(1 + z) (1 + n)
1
(32)
Plugging (32) into (31), we get
(1 +
1
) >
+ (1 )
(33)
33
Condition (33) is the same as (19) :
To obtain the impact of bubbles on aggregate consumption of workers at steady state,
we simply aggregate the worker’s budget constraint at period t
bc
w
t
+ bs
w
t
= bw
t
+ Rbs
w
t1
= [(1 + z)(1 + n)]
Using bs
w
= bw=(1 +
1
), at the steady state, we have
bc
w
=
1 +
R
(1 + z) (1 + n)
1
=(1 +
1
)
bw (34)
It is easy to show that the coe¢ cient for bw on the right side of (34) is positive. And since
bw = (1 ) (1 )
b
k
E
1
; we have @ bw=@
b
k
E
> 0. Hence, introducing housing reduces
aggregate consumption for the worker at the steady state.
Now we prove the welfare implication of housing for both the worker and entrepreneur.
For the worker, simply notice that their deposit rate is xed at R: Hence a reduction of
permanent income, bw; will reduce their lifetime utility. For the entrepreneur, the lifetime
utility can be expressed as
log (m
t
s
Et
) + log
E
t
s
Et
= log
E
t
k
Et
(1 + ) (1 )
+ log
E
t
k
Et
=
Et
= (1 + ) log
E
t
k
Et
log
Et
+ C (35)
where C is a constant as a function of parameters. Plugging the steady-state value of
E
t
and k
Et
into (35) ; we get
(1 + ) log
E
k
E
log
E
+ C
= (1 + ) log
1
1 +
1
E
(1 + z) (1 + n)
"
E
1
1 +
1
(1 + z) (1 + )
#
1
1
log
E
+ C
=
(1 + )
1
log
E
+
e
C
where
e
C is another constant as a function of parameters. Hence, introducing housing, i.e.
reducing
E
; reduces the welfare if
(1+)
1
> ; that is,
1 +
1
> 1 : Note that the
34
joint of participation and incentive constraint of the young entrepreneur implies m = y
E
>
w = (1 ) (1 ) y
E
; which gives the following parameter restriction > (1 ) (1 ),
or equivalently
+(1 )
> 1 : Therefore, with the assumption (19) ; introducing housing
will reduce the lifetime utility of the entrepreneur at the steady state.
Proof of Proposition 2: The proof of welfare implication for the workers and entrepre-
neurs along transition is straightforward. For the entrepreneur in the post-transition period,
we need to prove
@
h
@m
t
=@k
Et
+
E
t
+
E0
t
b
k
Et
b
k
Et
i
@
b
k
Et
< 0: (36)
In the post-transition period, since
b
k
Et
increases monotonically. (36) simply says that the
net marginal benet (loss) of an increase (decrease) in capital is higher when
b
k
Et
is smaller.
Using (31) and the denition of
E
t
; the left side of (36) is
@
h
@m
t
=@k
Et
+
E
t
+
E0
t
b
k
Et
b
k
Et
i
@
b
k
Et
= (1 )
2
(1 )
b
k
Et
2
1
< 0:
Proof of Lemma 1. We now prove that the share of entrepreneurial savings in housing
is constant over time. Using the housing market clearing condition, we have
(1
Et
)
1
1 +
1
(K
Et
)
(A
t
n
Et
N
t
)
1
= P
H
t
H (37)
Forwarding (37) by one period, and with (K
Et+1
)
(A
t+1
n
Et+1
N
t+1
)
1
= K
Et+1
E
t+1
= [ (1 )],
equation (37) can be rewritten as
1
Et+1
1
1 +
1
E
t+1
K
Et+1
(1 )
= P
H
t+1
H (38)
With the law of motion for capital (8) ; (38) can be rewritten as
1
Et+1
1
1 +
1
E
t+1
(1 )
Et
1 +
1
(K
Et
)
(A
t
n
Et
N
t
)
1
= P
H
t+1
H (39)
35
Dividing (39) by (37)for all t; we have
1
Et+1
1
Et
Et
1 +
1
E
t+1
(1 )
=
P
H
t+1
P
H
t
=
E
t+1
; (40)
or simply
1
Et+1
1
Et
Et
1 +
1
(1 )
= 1 (41)
Equation (41) is a rst-di¤erence equation capturing the dynamics of
Et
: One solution
to (40) is that
Et
=
(1 ) (1 +
1
)
; 8:
7.2 Allowing Entrepreneurs to Borrow against Housing
A potential remedy for credit misallocation is to allow access of E-…rms to bank credit. Note
that since the lending rate is xed and below the rate of return to housing, banks would not
be willing to lend to E-…rms at the low interest rate. Moreover, in China, entrepreneurs face
limited enforcement in debt repayment. Hence, banks can lend to E-…rms with housing (or
land) as collateral.
We assume that each young entrepreneur can borrow against his housing purchase at the
end of each period
R
E
l
Et
#P
H
t
h
Et
; 0 # 1 (42)
where the left-hand side of (42) is the bank loan (plus interest payment) to young entrepre-
neurs, which has to be less than or equal to a fraction # < 1 of the value of housing purchase.
In our benchmark economy, # = 0: We now consider a permanent increase in #: It is easy to
show that the law of motion for capital and housing now follow
K
Et+1
=
R
E
Et
R
E
# (1
Et
)
Et
K
Et
(43)
P
H
t
H
Et
=
(1
Et
) R
E
R
E
# (1
Et
)
Et
K
Et
(44)
where
Et
E
(1 )
1
1+
1
. Clearly, a change in # (expected or unexpected) ects the
entrepreneurial capital and housing demand via two channels: (i) a direct ect: an increase
36
in # increases the amount of borrowing by entrepreneurs and thus increases demand for
both capital and housing; (ii) an indirect ect via
Et
: since both the returns for physical
capital and housing is larger than the borrowing cost, R
E
; entrepreneurs will borrow to the
credit limit, which implies an increase in the share of housing in the asset portfolio held
by entrepreneurs, i.e.
Et
fall in responses to anticipated or unanticipated increases in #.
Accordingly to (44) ; this would reinforce the positive impact on housing demand.
37