The data are available to calculate the relative contribution of changes in real after-tax wages and market work time to changes in real after-tax income for the household groups.
The first entry gives that part of the percentage change in real after-tax income resulting from changes in the real after-tax wage rate, and the second entry gives that part of the percentage change in real after-tax income resulting from changes in market work time.
In contrast, if real after-tax income fell, with real after-wages falling but market work time rising, then it must be that real after-tax wages fell more, in percentage terms, than real after-tax income.
First, real after-tax wage changes were a negative contribution to changes in real after-tax income for a large majority (24 of 27 comparisons) of the cases over the 1972 to 1984 period.
Changes in market work time were a positive contribution to changes in real after-tax income in a large majority of the comparisons.
The major question is, which was the more important contributor to real after-tax income changes over the study period--changes in real after-tax wages or changes in market work time?