HOUSEHOLD INCOME OR HOUSEHOLD INCOME PER CAPITA IN WELFARE COMPARISONS*

Abstract

In studies of income distribution household income is the common measure of household welfare, although household per capita income is better since it automatically “corrects” for household size. Perhaps the continued use of the former is a consequence of the belief that in practice the two give very similar results. This paper shows that in many cases those results differ substantially. Policy prescription based on household income rather than household per capita income can be very defective. The paper compares results according to the two income concepts for Malaysian data. U.S. data are then used in a comparison over time.The disparity between the two Malaysian distributions is illustrated by their cross tabulation. A quarter of the households in the lowest forty percent of the household income distribution is in the upper three quintiles of household per capita income; and 10 percent of the same lowest forty are in the highest two quintiles of the second distribution. The paper also shows that the distribution of benefits from public education‐measured as the public costs of school years—is very inegalitarian if household income is used. The reverse occurs if household per capita income is used. Similar reversals occur in comparisons involving partitions by occupation and sex of head of household. Women‐headed households, for example, have sub‐mean household incomes but their household income per capita equals the mean. The paper also examines the differences in the age‐income profiles of the two distributions. It then considers whether the much discussed secular stagnation in U.S. measures of inequality is changed if household income per capita is used rather than the usual household income measure. Use of the per capita concept results in a slight decrease in U.S. inequality between 1947 and 1972. Appendix 2 explores how long term growth in per capita incomes and the associated changes in the size composition of households may affect measurements of inequality.