Across the country, women in their prime earning years, struggling with an unfriendly economy, are retreating from the workforce, either permanently or for long stretches.

They had piled into jobs in growing numbers since the 1960s. But that stopped happening this decade, and as the nearly seven-year-old recovery gives way to hard times, the retreat is likely to accelerate.

For the first time since the women's movement came to life, an economic recovery has come and gone, and the percentage of women at work has fallen, not risen, the Bureau of Labor Statistics reports. In each of the seven previous recoveries since 1960, the recovery ended with a greater percentage of women at work than when it began.

When economists first started noticing this trend two or three years ago, many suggested that the pullback from paid employment was a matter of the women themselves deciding to stay home -- to raise children or because their husbands were doing well. But now, a different explanation is turning up in government data, in the research of a few economists and in a congressional study, to be released today, that follow the women's story through the end of 2007.

After moving into virtually every occupation, women are being afflicted on a large scale by the same troubles as men: downturns, layoffs, outsourcing, stagnant wages or the discouraging prospect of a pay cut. And they are responding as men have, by dropping out or disappearing for a while.

Hard times in manufacturing certainly sidelined Tootie Samson of Baxter, Iowa. Nine months after she lost her job on a factory assembly line, Samson, 48, is still not working. She could be. Jobs that pay $8 or $9 an hour are easy enough to land, she said. But like the men with whom she worked at the Maytag washing machine factory, now closed, she resists going back to work at less than half of her old wage.

The study by the Joint Economic Committee of Congress cites the growing statistical evidence that women are leaving the work force "on par with men," and the potentially dire consequences for families.

"Women bring home about one-third of family income," said Rep. Carolyn Maloney, D-N.Y., the vice chairwoman of the committee. "And only those families with a working wife have seen real improvement in their living standards."

According to Department of Employment and Economic Data, the labor force participation rate for women in the nation is 59.3 percent while in Minnesota it is 67.6 percent.

The proportion of women holding jobs in their prime working years, 25 to 54, peaked at 74.9 percent in early 2000 as the technology investment bubble was about to burst. Eight years later, in June, it was 72.7 percent, a seemingly small decline, but those 2.2 percentage points erase more than 12 years of gains for women. Four million more in their prime years would be employed today if the old pattern had prevailed through the expansion now ending.

The pattern is roughly similar among the well-educated and the less educated, among the married and never married, among mothers with teenage children and those with children younger than 6, and among white women and black.

The women, in sum, are for the first time withdrawing from work with the same uniformity as men in their prime working years. Ninety-six percent of those men held jobs in 1953, their peak year. That is down to 86.4 percent today. But while men are rarely thought of as dropping out to run the household, that is often the assumption with women.

"A woman gets laid off and she stays home for six months with her kids," said Heather Boushey, a senior economist at the Joint Economic Committee. "She doesn't admit that she is staying home because she could not get another acceptable job."

Wage stagnation often discourages them from pursuing new jobs, said Lawrence Katz, a labor economist at Harvard. "While pay was rising solidly in the 1990s, you had women continuing to move into the work force," Katz said.

Pay is no longer rising smartly for women in the 25-to-54 age group. The median pay has fallen in recent years, to $14.84 an hour in 2007 from $15.04 in 2004, adjusted for inflation, according to the Economic Policy Institute. (The current median wage for men is $2 more.)

Not since the 1970s has that happened to women for so long a stretch. Nancy Folbre, an economist at the University of Massachusetts, said that because this is a new experience for them, "women may be even more reluctant than men to accept declining wages."