As the number of working women increased in recent years, so did the importance of their income to their families' economic well-being, according to a House Ways and Means Committee analysis.

The average inflation-adjusted income of the highest-paid female earner in each household rose 28.2 percent between 1979 and 1987.

Female earnings accounted for 29 percent of total household income in 1987, up from 24 percent in 1979. During the same period, comparable men's wages and salaries remained virtually unchanged, falling 0.1 percent, while total family earnings went up 6.4 percent.

But the poor saw a decline in earnings while the wealthier enjoyed big gains on average.

In the poorest two-fifths of families, the increase in women's income was less than the decline in men's earnings. As a result, total family income declined. Families in the middle two-fifths gained in total income only because the increase in female earnings was greater than the decline in male earnings.

But among the wealthiest 20 percent, earnings of both men and women increased and these families accounted for 80 percent of the increase in family incomes between 1979 and 1987, according to the committee's analysis.

Each 20 percentile grouping represents about 50 million families.

While women's income rose across the economic strata, the increase was much larger in wealthier families. Female earnings rose 2.9 percent among the poorest fifth, compared with 34.9 percent among the richest fifth of all American families.

The statistics are contained in the so-called Green Book, the House Ways and Means Committee's annual compilation of facts and figures concerning programs the panel oversees, including income and tax data. It is scheduled to be released Monday.

The volume, based on data from a wide range of federal agencies, is intended to help guide lawmakers as they write the nation's tax policy. It also provides a snapshot of how American families are faring financially and how various federal programs are affecting them.

It shows, for instance, that because of changes in federal assistance programs for which eligibility is based on income, 2.9 million more people were below the poverty line in 1988 than in 1979.

These changes include revisions in federal food stamp and housing programs and Aid to Families with Dependent Children benefits that have not kept pace with inflation, according to committee aides.

On the other hand, as a result of the 1986 overhaul of the tax code, tax payments pushed 1.6 million fewer below the poverty line in 1988 than in 1984, according to the committee's data. Federal tax payments in 1988 reduced the cash income of 857,000 Americans to below the poverty line, compared with 2.4 million in 1984 and 675,000 in 1979.

Economic growth, which narrowed the gap between rich and poor in the 1950s, widened it in the 1970s. Between 1950 and 1960, the greatest percentage growth was in lower-income groups. Between 1970 and 1980, though, the greatest growth was experienced by those in the top three-fifths.

Democrats who oppose President Bush's proposal to cut the rate at which capital gains are taxed as a boon for the rich will find ammunition in the Ways and Means volume.

It shows that realizations of capital gains have become an increasingly large source of income for the richest while having little impact on the incomes of most other Americans.

The very wealthiest taxpayers will receive on average 31.9 percent of their income from capital gains this year, the study projects, up from 26.5 percent in 1980 and 22.9 percent in 1977. For the bottom 90 percent of taxpayers, capital gains accounted for only about 1 percent of their income in each of those years.

Moreover, the tax burden on the top 1 percent of income earners has decreased since 1977, while it has increased on the middle one-fifth of taxpayers, according to the committee's report.

The wealthiest will pay an effective federal tax rate of 27.2 percent this year, compared with 27.1 percent in 1985 and 31.6 percent in 1980 and 1977. The middle one-fifth, on the other hand, will pay an effective rate of 20.3 percent this year, compared with 19.2 percent in 1985, 19.5 percent in 1980 and 17.5 percent in 1977.


FAMILY .................TOP..........TOP .........TOTAL

INCOME ................ MALE ...... FEMALE ...... FAMILY

RANKING ............... EARNER .... EARNER ...... EARNINGS

Lowest Fifth......... -17.9 ...... +2.9 ......... -10.5

Second Fifth......... -11.9 ..... +18.8 ........ - 3.7

Middle Fifth ......... -6.0 ...... +24.6 ......... +1.6

Fourth Fifth ......... -2.2 ...... +29.7 ......... +5.4

Fifth Fifth .......... +8.2 ...... +34.9 ........ +13.3

TOTAL ................ -0.1 ...... +28.2 ......... +6.4

Source: House Ways and Means Committee