Cross-sectional Facts for Macroeconomists: UK Richard Blundell and Ben Etheridge (University College London and Institute for Fiscal Studies) Preliminary Draft Fifth PIER IGIER International Conference Inequality in Macroeconomics: Facts and Theories November 2007 Layout for talk • • • • Basic UK data sources and issues Overall characterisation of the trends since 1978 Specific features of the dispersion and covariation How much can we learn about the decomposition of income risk from repeated cross-sections? – Key variance-covariance decompositions – Results from a simulated stochastic economy • Some conclusions – All underlying spreadsheets, figures and tables for the UK project are at www.ifs.org.uk/ 1 Data Series • Basic UK data for the period 1978 – 2005 – – – – – – Consumption Income Earnings Participation Hours Covariances for all these series over this period. • Income dynamics – All measures from 1991 • Wealth – Recent cross-sections only Data Sources and Issues • 1978 – 2005 is from consistent repeated crosssection household surveys – – – – Family Expenditure Survey (1969 onwards) Family Resources Survey (1993 onwards) Labour Force Survey (1978 onwards) Survey of Personal Incomes (tax records: 1994 onwards) • Household Panel Data (BHPS) from 1991 onwards – Low quality interval consumption questions – Use this mainly for income dynamics – Wealth data only in 1995 and 2000 surveys 2 Summary Facts #1 • Consumption and Income: – Income dispersion, for all measures, rose strongly in the 1980s, with some further rise in the late 1990s. – Consumption dispersion, for all measures, rose quite strongly in the early 1980s and then again, although at a slower rate, in the late 1990s. – The covariance between the two series rose monotonically until the late 1990s. – Strong growth in top percentiles in late 1990s – Cohort patterns show important life-cycle growth in dispersion Summary Facts #2 • Employment and Hours: – Secular decline in male participation until mid 90s • accentuated at later ages • accentuated for low education groups – Systematic cohort growth in female participation, strongest in mid and late 1980s. – Different employment and hours profiles between women in couples with children and single mothers • Strong growth in proportion of single mothers – Little change in variance of hours worked for men – Increase in the covariance of participation in couples 3 Summary Facts #3 • Earnings and wages: – Dispersion of male earnings rises, dispersion of male hourly wages rises at a slower rate. – Dispersion of female earnings is flat and then declines recently, dispersion of female hourly wages rises but at a slower rate than male hourly wages. – Covariance of earnings rises and then declines. – Covariance of hourly wages rises and then flattens. Some Figures and Tables 4 Figure 1a: Income and Consumption Dispersion 2.4 2.2 2 1.8 1.6 1.4 1.2 1 0.8 1978 1981 1984 1987 1990 1993 Var of log Equiv Consumption 1996 1999 2002 2005 Var of log Equiv Income Source: FES. Figure 1b: Income and Consumption: Variance-Covariance 0.6 0.75 0.7 0.5 0.65 0.6 0.4 0.55 0.3 0.5 0.45 0.2 0.4 0.1 0.35 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 Variance log Equiv Consumption Variance log Equiv Income Covariance Correlation, Right Axis Source: FES. 5 Figure 1c: Income Measures: Dispersion by time 0.9 0.8 0.7 0.6 0.5 0.4 Wages of Male Heads Gross Earnings 20 04 02 00 20 20 98 96 19 19 19 94 92 90 19 19 19 88 86 84 19 19 19 82 80 19 19 78 0.3 After-Tax Non-Financial Income Source: FES. Figure 1d: Income (after tax) Decomposition: Dispersion by time 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 SD of Log After-Tax Income Houshold Composition Age 04 20 00 02 20 98 20 19 96 19 94 19 92 19 90 19 88 19 86 19 82 80 84 19 19 19 19 78 0 Residual Education Region Source: FES. 6 Figure 1e: Income Inequality, by Cohort 0.6 0.5 0.4 0.3 0.2 0.1 0 25 27 29 31 33 35 37 39 41 1930s 43 1940s 45 47 49 51 53 55 57 59 1950s Source: FES. Figure 1f: Consumption Inequality, by Cohort 0.26 0.24 0.22 0.2 0.18 0.16 0.14 0.12 0.1 25 27 29 31 33 35 37 39 1930s 41 43 1940s 45 47 49 51 53 55 57 59 1950s Source: FES. 7 theoretical percentiles 5 8 6 7 9 Figure 1g: The distribution of log consumption: UK FES 95 75 25 3 4 0 .2 .4 .6 .8 observed density 1 5 3 4 5 6 7 observed percentiles 8 9 Standard Deviation of Logs: 0.4941 Skewness: 0.0192 Kurtosis: 0.0474 P-values: Kolmogorov-Smirnov: 0.1684 Skewness: 0.4113 Kurtosis: 0.0645 COHORT 1940-49, AGE 41-45 Source: Battistin, Blundell and Lewbel theoretical percentiles 5 7 9 6 8 Figure 1h: The distribution of log income: UK FES 95 75 25 3 0 .2 .4 .6 observed density 4 .8 1 5 3 4 5 6 7 observed percentiles 8 9 Standard Deviation of Logs: 0.4774 Skewness: -0.0130 Kurtosis: 0.1610 P-values: Kolmogorov-Smirnov: 0.0000 Skewness: 0.5705 Kurtosis: 0.0000 COHORT 1940-49, AGE 41-45 Source: Battistin, Blundell and Lewbel 8 theoretical percentiles 6 5 7 8 9 Figure 1i: The distribution of log consumption: UK FES 95 75 25 3 4 0 .2 .4 .6 .8 observed density 1 5 3 4 5 6 7 observed percentiles 8 9 Standard Deviation of Logs: 0.5348 Skewness: 0.0132 Kurtosis: -0.0030 P-values: Kolmogorov-Smirnov: 0.6692 Skewness: 0.6280 Kurtosis: 0.9192 COHORT 1940-49, AGE 51-55 Source: Battistin, Blundell and Lewbel Figure 2a: Overall Employment and Growth Rates 6% 90 5% 3% 70 2% 1% 60 0% Major Thatcher 50 Real GDP growth 4% -1% Blair -2% 2004 1999 1994 1989 -3% 1984 40 1979 Employment rates (%) 80 Year All Male Female Low skilled GDP growth 9 Figure 2b: Employment by education and gender, by year 1 0.95 0.9 0.85 0.8 0.75 0.7 0.65 0.6 0.55 19 78 19 80 19 82 19 84 19 86 19 88 19 90 19 92 19 94 19 96 19 98 20 00 20 02 20 04 0.5 Female - College Male - Leave at 18 Male - College Female - Compulsory Female - Leave at 18 Male - Compulsory Source: FES. Figure 2c: Employment by cohort and gender, by age 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 59 57 55 53 51 49 47 45 43 41 39 37 35 33 31 29 27 25 0.2 1925-29, Male 1935-39, Male 1945-49, Male 1955-59, Male 1965-70, Male 1925-29, Female 1935-39, Female 1945-49, Female 1955-59, Female 1965-70, Female Source: FES. 10 Figure 2d: Hours by education and gender, by year 50 45 40 35 30 25 Leave at 18, Male Leave at 18, Female 04 20 02 00 20 20 19 98 96 94 19 19 92 90 19 88 86 College, Male College, Female 19 19 84 19 19 82 80 19 19 19 78 20 Compulsory, Male Compulsory, Female Source: FES. Figure 2e: Variance-Covariance Structure of Participation 0.35 0.3 0.25 0.2 0.15 0.1 0.05 Var of Participation of Head Covariance 04 02 20 20 00 20 98 19 96 19 94 19 92 19 88 90 19 19 86 19 84 19 82 19 80 19 19 78 0 Var of Participation of Spouse Correlation Source: FES. 11 Figure 2f: Variance-Covariance Structure of Hours of Work 0.5 0.4 0.3 0.2 0.1 0 1978 1984 1981 1990 1987 1993 1996 2002 1999 2005 -0.1 Var of log Hours of Male Heads Var of log Hours of Female Spouses Covariance Source: FES. Figure 2g: Cross-section Employment over the Life-Cycle: Men 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 16 18 20 22 24 26 28 30 32 34 36 38 40 1975 42 44 1985 46 48 1995 50 52 54 56 58 60 62 64 66 68 70 72 74 2005 Source: LFS. 12 Figure 2h: Cross-section Employment over the Life-Cycle: Women 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 16 18 20 22 24 26 28 30 32 34 36 38 40 42 1975 44 1985 46 48 1995 50 52 54 56 58 60 62 64 66 68 70 72 74 2005 Source: LFS. Figure 2i: Employment Rates for Women by Demographic Group 0.9 0.8 0.7 0.6 0.5 0.4 0.3 1978 1983 singlenokids 1988 singlekids 1993 1998 couplenokids couplekids 2003 13 Figure 3a: Variance-Covariance Structure of Earnings 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 1978 1981 1984 1987 1990 1993 1996 1999 2002 2005 Variance of log Earnings of Head Variance of log Earnings of Spouse Covariance Correlation Source: FES. Figure 3b: Variance-Covariance Structure of Wages 0.35 0.3 0.25 0.2 0.15 0.1 0.05 0 1978 1981 1984 1987 Var of log Wages of Male Head 1990 1993 1996 1999 2002 Var of log Wages of Female Spouse 2005 Covariance Source: FES. 14 Figure 3c: Normalised Log wage inequality by cohort over age 1.2 1.1 1 1921-1925 1931-1935 1941-1945 0.9 1951-1955 1961-1965 1971-1975 0.8 0.7 64 60 62 56 58 52 54 48 50 44 46 40 42 36 38 32 34 28 30 24 26 20 22 0.6 Income dynamics • Consider the simple decomposition: ln Yi , a ,t = Z i', a ,t λ + f i + yiP, a ,t + yiT, a ,t where yiP, a ,t = yiP, a −1,t −1 + ζ i , a ,t • permanent component following a martingale process • and a transitory or mean-reverting component yT = v w ith v it = q ∑θ j=0 j ε i , a − j ,t − j and θ 0 ≡ 1. • implies a simple structure for the autocovariance of Δy ≡ lnY - Z' λ • variance-covariance results from BHPS in Tables I a-c. 15 Table Ia: The Covariance Structure of Wage of Male Head Year var(∆yt) cov(∆yt,∆yt+1) cov(∆yt,∆yt+2) cov(∆yt,∆yt+3) 1994 0.0536 (.0041) 0.0609 (.0058) 0.0459 (.0026) 0.0435 (.0020) 0.0466 (.0020) 0.0423 (.0024) 0.0477 (.0026) 0.0502 (.0026) 0.0459 (.0022) 0.0480 (.0031) 0.0460 (.0026) -0.0106 (.0017) -0.0102 (.0019) -0.0104 (.0014) -0.0094 (.0014) -0.0100 (.0015) -0.0098 (.0018) -0.0169 (.0018) -0.0150 (.0015) -0.0137 (.0015) -0.0151 (.0016) - -0.0020 (.0015) -0.0003 (.0016) -0.0006 (.0013) 0.0000 (.0012) -0.0001 (.0015) -0.0005 (.0015) 0.0008 (.0014) -0.0015 (.0016) 0.0009 (.0017) - -0.0007 (.0015) 0.0019 (.0016) -0.0009 (.0013) 0.0000 (.0013) 0.0029 (.0016) -0.0001 (.0015) 0.0001 (.0016) 0.0004 (.0016) - 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Variance of log residuals, BHPS Table Ib: The Covariance Structure of HH Earnings - BHPS Year var(∆yt) cov(∆yt,∆yt+1) cov(∆yt,∆yt+2) cov(∆yt,∆yt+3) 1994 0.1458 (.0080) 0.1319 (.0068) 0.1022 (.0052) 0.1301 (.0066) 0.1265 (.0064) 0.1183 (.0059) 0.1078 (.0051) 0.1121 (.0057) 0.1061 (.0053) 0.1171 (.0063) 0.1280 (.0069) -0.0437 (.0051) -0.0315 (.0044) -0.0291 (.0041) -0.0319 (.0044) -0.0305 (.0041) -0.0275 (.0036) -0.0235 (.0034) -0.0239 (.0036) -0.0180 (.0037) -0.0314 (.0045) - 0.0063 (.0044) -0.0004 (.0045) -0.0051 (.0036) -0.0042 (.0044) -0.0010 (.0036) -0.0020 (.0034) -0.0022 (.0033) -0.0144 (.0042) -0.0037 (.0039) - -0.0050 (.0045) -0.0048 (.0038) -0.0019 (.0034) -0.0077 (.0036) 0.0006 (.0038) 0.0046 (.0031) 0.0117 (.0041) -0.0044 (.0041) - 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Variance of log residuals, BHPS 16 Table Ic: The Covariance Structure of HH Income - BHPS Year var(∆yt) cov(∆yt,∆yt+1) cov(∆yt,∆yt+2) cov(∆yt,∆yt+3) 1994 0.0990 (.0043) 0.1013 (.0044) 0.0842 (.0034) 0.0906 (.0037) 0.0890 (.0037) 0.0852 (.0035) 0.0899 (.0039) 0.0864 (.0039) 0.0861 (.0037) 0.0936 (.0044) 0.0965 (.0048) -0.0276 (.0030) -0.0261 (.0027) -0.0227 (.0025) -0.0243 (.0026) -0.0269 (.0026) -0.0222 (.0026) -0.0260 (.0026) -0.0256 (.0028) -0.0219 (.0029) -0.0293 (.0033) - 0.0037 (.0026) -0.0015 (.0028) 0.0000 (.0024) -0.0032 (.0025) -0.0042 (.0025) -0.0024 (.0024) 0.0007 (.0026) -0.0090 (.0029) -0.0030 (.0028) - -0.0072 (.0030) -0.0027 (.0025) -0.0007 (.0024) 0.0005 (.0023) 0.0000 (.0026) 0.0025 (.0025) 0.0050 (.0027) -0.0010 (.0030) - 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 Variance of log residuals, BHPS How much can we learn from repeated cross-sections about income risk? • With CRRA preferences, the Euler equation is: Citβ −1 = 1 + rt Et e ΔZ it +1ϑ Citβ+−11 1+ δ • We show that this can be approximated by: Δ ln Cit ≈ Γit + ΔZ it 'ϑ + π itζ it + γ tLπ it ε it + ξit • Implies a set of over-identifying cross-section (and panel) moments 17 Identifying the Decomposition of Shocks • To judge the ability of the model to identify the underlying parameters and processes, simulate a stochastic economy. • In the base case the discount rate δ=0.02, also allow δ to take values 0.04 and 0.01. Also a mixed population with half at 0.02 and a quarter each at 0.04 and 0.01. • In such cases the permanent variance follows a two-state, first-order Markov process with the transition probability between alternative variances. • For each experiment, simulate consumption, earnings and asset paths for 50,000 individuals. • Obtain estimates of the variance for each period from random cross sectional samples of 2000 individuals for each of 20 periods: Figure 4a. Figure 4a: A Simulated Economy, permanent shock variance estimates 0.016 0.012 0.008 0.004 0 1 2 3 4 5 truth 6 7 8 9 approximation 10 11 12 impatient 13 14 15 16 17 18 19 heterogeneous Source: Blundell, Low and Preston (2005) 18