It looked pretty good for young women's earnings in 2011. The pay gap separating women and men aged 25 to 34 was the smallest ever recorded by the Pew Research Center, with young women earning 97 cents for every dollar paid their young male counterparts. For the rising generation of U.S. workers, at least, there was very nearly income equality.

Then things started going backwards. By 2015, the pay gap for 25- to 34-year-olds had widened to 90 cents for every man-earned dollar in that demographic, according to new data from Pew. What happened?

It turns out that what looked like good news for young women earlier this decade was mostly just bad news for men. "During the recession, men were much harder hit than women in terms of employment losses. They were more likely to be located in jobs and industries that took a big hit," said Rakesh Kochharm, an economist at Pew. "Rather than women catching up, you're seeing a return to the historical level."

Women didn't catch up—men slid backwards.
 
Even taking the recession blip into account, women of all ages haven't made much progress in the last decade. The gender-pay gaps for all women and for young women both hover around the same numbers they did in 2005. Pew has found that a woman today makes 83 cents to a man's dollar, a finding that has stayed consistent over the last 10 years. That's also consistent with the Bureau of Labor Statistics' findings.

The pay gap for young women is relatively small when compared to that of women in general because the American workplace punishes women with kids. Young men and women enter the corporate pipeline at the same rates, according to research from McKinsey and Lean In. One survey from Hired even found that women make 2 percent more than men for entry-level positions. Yet women make up only 17 percent of C-suite positions, McKinsey and Lean In found.

Women who have children tend to get pushed out of the workplace because of a lack of flexible schedules and paid parental leave policies. Those who stay in the workforce face what's known as the "motherhood penalty." For every child a woman has, she loses 4 percent in lifetime earnings, a figure purely attributable to bias. New moms come back from leave to fewer responsibilities. When a woman leaves early to pick a kid up from school, she gets judged.

Men, on the other hand, get a "fatherhood bonus"—a 10 percent bump in earnings for each child.

Paid parental leave policies and flexible schedules would help new moms integrate into the workforce. Neither of those things are happening, so progress reaching pay parity has stagnated. In the last decade, workplaces have reduced their parental leave policies. Even if that trend doesn't push women out of the workforce, rigid schedules can make it difficult for women to work the long hours required to make up for the wage gap.

At this point, most jobs still reward long hours—something people without kids, or most parental responsibilities, can do. "There seems to be a premium placed on working longer hours, which men are more apt to do," said Kochharm.

This article was provided by Bloomberg News.