Women today are working harder and earning more money than their mothers at the same age, and that's helped some of the nation's poorest families move up the economic ladder.
Still, a new Pew Charitable Trusts report finds that men's earnings continue to be the more important factor in bulking up the family paycheck.
"Family economic mobility continues to be driven by the earnings of men, despite (the) significant gains women have made," said Diana Elliott, a research officer with Pew's Economic Mobility Project.
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For example, today's daughters still haven't caught up with their fathers. The researchers found that the median—or midpoint—of hourly wages for working women today is still lower than it was for their fathers, after adjusting for inflation.
That's true at every rung of the economic ladder, Elliott said, and it wasn't true of sons.
Pew's analysis of government data finds that working women who were around age 40 in the 2000s earn nearly three times as much as working women who were around age 40 in the late 1960s and early '70s after adjusting for inflation.
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That's partly because the current generation of prime-age working women are putting in longer hours than their mothers—an average of 34 hours a week versus 24 hours in the previous generation.
It's also because they are earning more money. The current generation is earning $19 an hour on average, as compared with an inflation-adjusted $10 an hour for the women in the past generation.
Elliott said the increased time women are spending at work has had the most significant effect on the nation's poorest families. The researchers found that the share of couples who started on the bottom rung of the economic ladder and moved up to the middle or higher were 11 percentage points higher because women put in more time at work.
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For some families, however, all that extra time women are spending at work is just enabling the family keep their place on the economic ladder, the researchers found.
"The biggest movement upward was among those that were starting at the bottom," Elliott said.