The Decline of Income Inequality in China: Assessments and Explanations*
Guanghua Wan School of Economics Chongqing Technology and Business University 19 Xuefu Avenue, Nan’an District Chongqing, China, 400067 [email protected] Ting Wu Party School Tianjin Binhai Committee of CPC 540 Jiatai Road, Binhai New Area Tianjin, China, 300450 [email protected] Yan Zhang School of Economics Chongqing Technology and Business University 19 Xuefu Avenue, Nan’an District Chongqing, China, 400067 [email protected]
Abstract This paper shows that the trend of worsening income distribution in China has been reversed. We ascertain the robustness of this decline using five nationwide household survey and different inequality indicators. Attempts are then made to uncover the underlying reasons. Major findings include: (1) The decline is largely due to improvement in the distribution of transfer income although its share in the total income is small and diminishing; (2) Occupational income, particularly its component of wage income, plays an important role; and (3) Other drivers include the expansion of the middle-income group, rapid urbanization, and the shrinking disparity within Eastern China.
1. Introduction
Inequality is a major socioeconomic issue in China (Wan 2008; Wang, Wan, and Yang 2014). Its consecutive declines were noticed a few years ago (Wan 2013) but have re- ceived little analytical attention since then. The lack of research interest may be caused by uncertainty—whether this decline is part of the usual fluctuations or the beginning of a
* The authors gratefully acknowledge financial support from the Natural Science Foundation of China (Project no. 71703088) and Shanghai Pujiang Program (Project no. 17PJC045). Yan Zhang is the corresponding author for this paper.
Asian Economic Papers 17:3 © 2018 by the Asian Economic Panel and the Massachusetts Institute of Technology doi:10.1162/ASEP_a_00640
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new long-term trend. If one could confirm this trend, it is important to uncover the relevant driving factors.
This paper attempts to ascertain the robustness of the declining trend of income inequality by using different inequality measures and different databases. The data sets include the China Health and Nutrition Survey (CHNS); China Household Income Project (CHIP), China General Social Survey (CGSS), China Family Panel Studies (CFPS), and China Health and Retirement Longitudinal Survey (CHARLS). The inequality measures used in- clude the Theil index, the mean log deviation (MLD), the Gini coefficient, and the Atkinson index (Wan 2006).
In related work, using CHIP and CFPS data, Kanbur, Wang, and Zhang (2017) confirmed the decline and conducted several decomposition analyses. They found that the urban– rural gap peaked in 2004, the coast–inland disparity peaked in 2009, and the narrowing- down of wage distribution is the major inequality-reducing contributor. The authors merged two data sets, however—CHIP (1995–2007) and CFPS (2010–14)–whose con- sistency is debatable. For example, whereas CHIP consists of fewer than 40 percent of households from Eastern China in its 1995 and 2013 waves, around 50 percent of CFPS observations are from Eastern China in 2010 and 2014 (detailed results shown in Figure 7 later in the paper). As another example, the growth incidence curve (GIC) based on CFPS (2010–14) produces a broadly inverted U-pattern, whereas the GIC based on CHIP (2007– 13) exhibits a reverse S-shape. This data issue might be the cause for their very high Gini estimates for income components (0.583–1.128).
Relying on the CHIP data, Zhuang and Li (2016) asserted that factors driving the inequality decline include decreased skill premium, increasing share of labor income, and the falling income gaps between urban–rural areas and across regions. These assertions were made with little analytical evidence. Also using CHIP data, Li (2016) attempted to confirm the trend of inequality decline by estimating the Gini index and the income mobility index, and then plotting the GIC. His findings were inconclusive as six different disparity indicators he used showed different trends. For example, the top–bottom 10 percent income ratio, the business versus wage income ratio, and the labor share demonstrate inequality increase, whereas the growth of income by groups, the Gini coefficient, and mobility estimates show inequality decline.
In addition, several papers mentioned but did not analyze the recent inequality declines. These include Zhang (2015), Li et al. (2016), Fan, Kanbur, and Zhang (2011), Chan, Zhou, and Pan (2014), and Lee (2013).
Our paper departs from the existing literature in the following aspects. First, we fo- cus on explanations that are lacking in the literature by conducting extensive analyses
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and decompositions. Second, as many data sources as possible are used to ensure ro- bustness of results and conclusions. Third, fresh and important findings are generated. For example, we find that transfer income is the main contributor to overall inequal- ity decline, whereas Kanbur, Wang, and Zhang (2017) concluded that wage income is more important.
The rest of the paper is organized as follows. Section 2 assesses the robustness of the declin- ing trend of income inequality. Section 3 conducts preliminary analyses to uncover reasons of the declining inequality, using growth incidence curves. To further identify reasons or factors driving the recent inequality decline, Section 4 undertakes various decompositions. Finally, Section 5 concludes.
2. Is income inequality in China really declining?
This section presents inequality estimates using different indicators as well as differ- ent databases. As is known, different inequality indicators are sensitive to different seg- ments of the Lorenz curve and different data sets could generate different findings. This section will also conduct a stochastic dominance analysis by plotting and comparing Lorenz curves.
2.1 Estimating different inequality indicators Based on the five data sets, Figure 1 depicts inequality trends using different inequality indicators. The results show that although the turning point differs slightly, the increas- ing trend since the mid 1980s peaked between 2006 and 2010 irrespective of data set and inequality indicator used except when using the CFPS data. In the latter case, the esti- mates of the MLD show no turning point. And the estimates of the Atkinson index indi- cate that the turning point occurred in 2012, later than the other indicators show. This is possibly because the MLD is more sensitive to low-income observations and CFPS collects more low-income observations than other databases (see more details in Section 2.2 on the Lorenz curve).
The solid lines in Figure 1 correspond to the CHNS database, which was collected every two years from 1989 to 2011. They all exhibit an inverted U-shape, with inequality peaking in 2006.
The dotted lines correspond to the CHIP database, which was collected approximately every five years from 1990 to 2013. They show that inequality peaked in 2007. The Gini estimate increased from 0.32 in 1990 to 0.50 in 2007. Other measures show declines from 1994 to 2001, followed by increases from 2002 to 2007 before declining again. For example, the Gini estimates decreased successively from 0.5 in 2007 to 0.42 in 2013.
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Figure 1. Income inequality in China: 1989–2014
Source: Authors’ calculation. Data from CHNS (1989–2011), CHIP (1995–2013), CFPS (2010–14), CGSS (2006–13), CHARLS (2011–13).
The lines with triangles correspond to the CFPS database. In this case, the Gini and Theil estimates declined steadily between 2010 and 2014, the MLD estimates rise, and the Atkin- son estimates increased from 2010 to 2012 and then declined.
The dashed lines with dots or diamonds show results from the databases of CGSS and CHARLS, respectively. They all share a similar trend of declining inequality. This is due to the late start of these two surveys, starting after China’s inequality began to decline.
2.2 Lorenz curve To confirm the inverted U pattern seen in Section 2.1, and to explore why CFPS data give inconsistent results, we plot various Lorenz curves. In Figure 2, the solid Lorenz curves correspond to the year when the relevant survey began, the short-dashed curves correspond to the year when inequality estimates peaked, and the long-dashed curves
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Figure 2. Lorenz curves based on different data, 1989–2014
Source: Authors’ calculation. Data from CHNS (1989–2011), CHIP (1995–2013), CFPS (2010–14), CGSS (2006–13), CHARLS (2011–13).
correspond to the latest year. When using the CFPS data, the three curves correspond to 2010, 2012 and 2014, respectively.
Several findings are worth mentioning. First, for the CHNS, CHIP, and CGSS data, the short-dashed curves (representing the peak of inequality) all lie in the bottom-right, con- firming the peaking of inequality in the relevant year. The declines afterwards primarily stem from the declining income shares of high-income groups. In the earlier phase of rising inequality, the income shares of high-income groups increased, the share of middle-income groups dropped, and the share of low-income groups did not change.
Second, for the CFPS data, the Lorenz curves for 2010 and 2012 largely overlap, indicating little change in inequality over these two years. The situation changed in 2014, however. Although the income shares rose for the middle- and upper- income groups (the long- dashed curves for these two groups moved closer to the 45-degree diagonal line), those
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for the low-income groups declined slightly. Overall, the level of inequality in 2014 was lower than in the earlier two years.
Third, for the CHARLS data, the Lorenz curve for 2013 moved slightly closer to the diago- nal line than the 2011 curve, indicating an improvement in income distribution.
3. Preliminary analytical results using the GIC tool
This section examines changes in income shares of different income groups using the growth incidence curve (GIC). Proposed by Ravallion and Chen (2003), the GIC is widely applied to gain insights into changes in income distribution (Lin 2003) or pro-poor growth (Chen and Wang 2001; Honohan 2008; Goh, Luo, and Zhu 2009; Huang and Quibria 2013). The GIC is defined as
= yt (p) − , gt (p) 1 (1) yt−1(p)
where the subscript t indicates year, g(p) is the rate of income growth for the pth percentile population, and y denotes income. If data span multiple periods, the average income growth rate can be calculated as
1/n = yn(p) − , gavg(p) 1 (2) y0(p)
where n is the number of intertemporal periods, and the subscript 0 indicates the base pe- riod. Insights can be gained by comparing income growth for different income groups (rep- resented by the percentile of the population) on the GIC. The higher the income growth rate, the greater the rise in the income share of the relevant group, and vice versa.
3.1 GIC of total income We divide the sample into 12 subsamples: the poorest 5 percent, 10 percent, 20 percent, 30 percent, then the middle group of 40 percent, 50 percent, 60 percent, 70 percent, the richer 80 percent, 90 percent and 95 percent, and the top 5 percent. Figure 3 shows the GICs for the inequality rise phase (left) and the decline phase (right).
The results from the CHNS data show that: (1) In the inequality-rising phase of 1989–2006, the GIC sloped upwards monotonically, implying that the richer the household, the higher the income growth. The richest 5 percent achieved an average rate of income growth of 6.75 percent, whereas this rate for the poorest 5 percent was only 2.09 percent, which is 2.45 percentage points lower than the average of the whole sample. (2) In the inequality- declining phase of 2006–11, the GIC shows an inverted U-shape, meaning that the middle
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Figure 3. GICs of total income, by different data sets
Source: Authors’ calculation. Data from CHNS (1989–2011), CHIP (1995–2013), CFPS (2010–14), CGSS (2006–13), CHARLS (2011–13).
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class1 gained more than others, at 7.28 percent, significantly higher than the sample aver- age. The top 5 percent achieved the lowest growth, averaging 3.33 percent per annum, and the growth rate was 3.7 percent for the poorest 5 percent. A growing middle class appears to be underlying the improvement in income distribution.
The results from the CHIP data show that: (1) In the phase of rising inequality (1995–2007), the GIC is like that of CHNS. The wealthiest 5 percent recorded an average income growth of 7.09 percent, 1.47 times the overall average growth of 4.83 percent. Whereas the top 15 percent of households experienced above-average growth, the remaining 85 percent ex- perienced below-average growth. Those located in the bottom 15 percent experienced negative growth, averaging –6.83 percent. This phase can be characterized as a period of “pro-rich” growth. (2) In the period of inequality decline (2007–13), the sample average growth rate was 5.54 percent. Different from the results based on CHNS, the decreasing trend of the GIC is monotonic: The richer the household, the lower the income growth. For example, the richest 5 percent grew annually by only 2.12 percent, whereas this rate is 6.98 percent for the middle-income group, slightly higher than CHNS data show. The declining phase demonstrates the feature of typical “pro-poor” growth.
The results from the CGSS data show that: (1) In the phase of worsening income distri- bution (2006–08), the GIC displays an increasing trend. Income for the richest 5 percent grew at 2.69 percent, whereas the bottom 85 percent reported lower than average growth. As with the CHIP data, the growth rate of low- and middle-income families is negative, with about 65 percent of households experiencing negative income growth. This may be related to the adverse impact of the global economic crisis on the middle class, whose in- come dropped by 1.26 percent, as indicated by the notch on the GIC. (2) The GIC fluctuates slightly during the period of inequality decline (2008–13). The income of the middle-class grew by 4.83 percent, relatively higher than the average of other groups (4.29 percent). This is like the results based on CHNS, in which the growth of middle-income groups is the main driver for improving distribution. Unlike what other data show, however, the richest 15 percent in CGSS enjoyed a 4.29 percent growth rate, which is identical to the sample average.
The results from the CFPS data show that the growth rate of middle-class was significantly higher (6.44 percent) than that of other groups during the period of inequality decline (2010–14). This feature is common to CHNS and CGSS, confirming the role of an expanding middle-class in improving incomes distribution. The bottom 5 percent experienced nega- tive growth, however, which could explain why the MLD based on CFPS rose.
1 The middle class or middle-income group refers to households whose average income falls into the range of the 25th to 85th percentile of the whole sample.
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The results based on the CHARLS data are almost identical to those based on CHIP (2007– 13). The growth rate of the poor is much higher than that of the middle- and high-income groups, exhibiting “pro-poor” feature.
To sum up, a worsening income distribution can be largely accounted for by the relative losses of the poor in sharing the growth dividend in the earlier period. And the recent de- cline in inequality is mainly attributable to the expansion of the middle-class. One worri- some finding is that even in the period of inequality decline, the growth rate of the poor remains low, and often lower than that of the wealthy.
3.2 GICs of income components This section serves two purposes. First, it helps identify the role of transfer income in af- fecting income distribution. The transfer income mainly comprises government price sub- sidies, and provision of public pension and social assistance. Second, it may shed light on whether China has reached the Lewis turning point by examining the distributional trend of labor income.
According to Lewis (1954), in the early period of takeoff, there is unlimited supply of surplus rural labor to the urban factor market, meaning stagnant labor income or wage growth for rural-to-urban migrants. Because the native urbanites are likely to en- joy the usual wage growth, income disparities in the urban sector tend to enlarge. Af- ter reaching the Lewis turning point, disparities become stable or smaller due to the depletion of the surplus labor in the rural areas. Note, however, that labor income is an evolving concept in transition economies like China and it contains receipts other than wages. Therefore, here we examine distributions of both wage and, more broadly, occupational income.2
Different surveys adopt different income definitions. It is thus necessary to adjust and merge data to minimize inconsistency of data from different surveys. In this paper, we use CHNS as the benchmark and classify total income from CHNS into four components: wage, business income, transfer income, and other income. This classification is in line with that of CHIP (1995–2013) and CFPS (2010–14). CGSS (2006–13) does not provide ob- servations on component incomes. They only distinguish earnings from other incomes. CHARLS (2011–13) categorizes incomes into quite a few components, however observa- tions for component income are mostly missing. Thus, we group these income compo- nents into occupational income and other incomes, where occupational income is the sum
2 Occupational income consists of wage and business income. Wage refers to the remuneration paid to employees for work performed or service provided. Business income refers to the gain obtained from business activities.
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of wage and business income. Figures 4 and 5 plot the GICs of component incomes from CHNS and CHIP, respectively.
The following findings are discernable from Figure 4: (1) Inequality of occupational in- come, including wage and business income, declined. Its growth for middle- and lower- income groups was significantly higher than that for the wealthy. As the most important component of income in China (see Figure 6) with its share growing over time, improving distribution of occupational income plays a vital role in driving the trend of overall income inequality. (2) The distribution of occupational income improved slightly in the period of inequality decline (2006–11) when the middle-class gained more than others. This could be the main reason for the drop in the overall income inequality. (3) The distribution of trans- fer income significantly improved. The growth rate of government transfers is much higher for the poor and reduced considerably for the rich. (4) Figure 6 shows a small share of other income that naturally exerts little effect on the overall income distribution. From Figure 4, in the phase of rising inequality, the growth rates of other income for different groups are roughly the same. In the phase of inequality decline, except for the bottom 15 percent, who enjoyed slightly higher growth of other income, the remaining 85 percent see little differ- ence in their growth rates of other income.
Figure 5 displays the GIC for income components based on CHIP database. The results are broadly consistent with those from Figure 4, indicating that the improvement of occu- pational income distribution is the main driver for the overall inequality decline. More- over, both CHNS and CHIP show that the transfer income becomes more pro-poor in the phase of inequality decline, although the shapes of GICs differ. The growth rate of trans- fer income decreases monotonically with income quantiles in CHNS, whereas in CHIP it appears higher for middle classes than other groups.
4. Decomposing income inequality and its changes
This section uses the MLD index and the Gini coefficient to explore sources of inequality and its changes. Suppose the sample can be divided into G population subgroups; the MLD index can then be expressed as:
G G = + pg , MLD pgMLDg pgLog v (3) g g=1 g=1
v where pg is the population share of subgroup g, g is the corresponding income share, G MLDg is MLD index within group g. g=1 pgMLDg is the sum of income disparity within G pg each group, and = p Log( ) is the income inequality between subgroups. The former is g 1 g vg often termed within-group inequality and the latter between-group inequality.
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Figure 4. GIC of component income: CHNS
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Figure 5. GIC of component income: CHIP
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Figure 6. Composition of total income
Source: Authors’ calculation based on CHNS (1989–2011) and CHIP (1995–2013).
According to Schauer (1996), a change in the MLD index can be expressed as:
= + + pg + pg MLD pgMLDg pg MLDg pgLog v pg log v g g ≈ + + λ − λ + v − pgMLDg pg MLDg k log ( k ) pg g pg log ug
contribution of mobility contribution of changes of within−group inequality = + λ − λ + MLDg k log ( k ) pg pgMLDg
− contribution of changes of between group inequality + v − , g pg log ug (4)
Where the overbar indicates the average of the relevant variable in the beginning and end v periods. λ = g ; u is the mean income for group g. k pg g
Conversely, suppose total income consists of K components, the Gini coefficient G can be expressed as (Wan 1998):
K = , G SiCi (5) i=1
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where Si is the share of the i-th component in total income, and Ci denotes its concentration index.
A change in the Gini coefficient can be decomposed based on equation (5):
K K = − G Sit+1Cit+1 SitCit i=1 i=1
K K = + , Cit Si Sit Ci (6) i=1 i=1