In September 1990, the Census Bureau released a report entitled Measuring the Effect of Benefits and Taxes on Income and Poverty: 1989 (Series P-60, No. 169-RD). That report contained detailed jnformation on the incremental effect of benefits and taxes on income and poverty for 1989, along with summary statistics from 1988 and 1987. This report contains supplemental detailed estimates for 1988 and 1987 (comparable to the detailed estimates for 1989 as shown in series P-60, No. 169-RD).

For a description of the definitions of income used in the report and the measurement issues involved with the inclusion of taxes and benefits on the income definition, see the text to series P-60, No. 169-RD. That report also contains descriptions of the methods used to value noncash benefits (appendix B) and simulate taxes (appendix C) and capital gains.

The data shown here are based on estimates from the Current Population Survey for March of 1988 and 1989. All survey data are subject to sampling variability and nonsampling errors, such as data collection design flaws, respondent classification and reporting errors, and data processing mistakes. The Bureau has taken quality control measures to minimize nonsampling error. For more information on the sample design, estimation procedure, and accuracy of the data, see Current Population Reports, Series P-60, No. 169-RD.

Parameters used to calculate standard errors differed somewhat between March 1988, 1989, and 1990. Appendix C of Money Income and Poverty Status in the United States: 1989 (Series P-60, No. 168) contains the appropriate factors to adjust March 1990 parameters for these earlier years.

The appendix of this report contains data on the share of income received by each fifth by income definition for 1988 and 1987. These data are comparable to the 1989 figures that appeared in table B of series P-60, No. 169-RD.