Women are making significant gains in vying for higher-paying managerial and technical positions.
A new study shows the number of women earning $100,000 a year or better more than tripled during the past decade.
In 2001, 861,000 women earned $100,000 or more, compared with just 242,000 women in 1991, according to federal wage and salary data analyzed by the Employment Policy Foundation, a Washington research organization funded by business and foundations.
That was an increase of 256 percent for top female earners during the 1990s economic boom. There was a similar increase in the number of women in the next wage bracket, those earning between $80,000 and $99,999.
Far more men - 4.3 million - still earn above $100,000. And the wage gap between the sexes persists. Women were paid, on average, about 77 cents for every dollar paid to men in 2002.
But foundation economist Regina Powers, who conducted the wage research on U.S. Bureau of Labor Statistics data, said the numbers provide "solid evidence" that women are making inroads into the upper echelon, because of a combination of more education and greater opportunity.
Inflation is not responsible for the gains, because all wage figures were adjusted for inflation and expressed in 2001 dollars.
"I'm not trying to tell you that we've got 50-50" equality with men, she said, "but the point is that from '91 to 2001 women made great strides."
Almost one in three women who entered the labor force during the 1990s earned more than $60,000, Powers said.
The study also shows that the number of low-paid women shrank during the decade as a proportion of all working women. While there are 28 percent more women working today than in 1991, their numbers in one low-wage category - those earning $20,000 to $39,999 - increased by 23 percent.
"The shift is toward the higher-end earnings brackets," Powers said.
The data cover only full-time payroll workers and exclude women entrepreneurs who start their own businesses. The high-paid positions are typically white-collar executive, managerial or technical jobs.
Women are making more money for several reasons, said Paul Harrington, an economist with the Center for Labor Market Studies at Northeastern University.
They are becoming more educated, working longer hours, and moving into well-paying fields, whether finance or biotechnology, once dominated by men. Today, one in four engineering graduates are women, for example, up from one in six in 1990, Harrington said.
Also, some occupations historically dominated by women are suffering labor shortages, which have driven up wages in those fields. Nurses are a prime example.
Powers said there also are more opportunities available today.
"Women 30 years ago faced lots of barriers. That's not to say the barriers don't exist, but as a society we're moving forward and as time goes on those should diminish more and more."
But women's gains should not be overstated, because there are still far fewer women than men benefiting from economic growth, Harrington said. "You're getting big rates of change but on a smaller base."