It must be frustrating for the “women’s movement” — women just won’t cooperate. A new Pew study shows more and more women are staying at home with their children, or working part-time, rather than “leaning in” and trying to “have it all.”

“The share of mothers who do not work outside the home rose to 29 percent in 2012, up from a modern-era low of 23 percent in 1999, according to a new Pew Research Center analysis of government data,” Pew reports. “This rise over the past dozen years represents the reversal of a long-term decline in ‘stay-at-home’ mothers that had persisted for the last three decades of the 20th century. The recent turnaround appears to be driven by a mix of demographic, economic and societal factors, including rising immigration as well as a downturn in women’s labor force participation, and is set against a backdrop of continued public ambivalence about the impact of working mothers on young children.”

That’s a lot of information to unpack. But let’s start with the basics. Almost a third of adult women are not working at all. True, many are out of work and can’t find jobs to suit them, but according to Pew, a full 85 percent say they’re at home because they choose to be.

“The largest share consists of ‘traditional’ married stay-at-home mothers with working husbands,” Pew explains. “They made up roughly two-thirds of the nation’s 10.4 million stay-at-home mothers in 2012. In addition to this group, some stay-at-home mothers are single, cohabiting or married with a husband who does not work.”

A group that gets a lot of attention is the percentage of stay-at-home moms who are considered affluent. These women have educations (often advanced college degrees) and marketable skills, but they would rather be at home with their children.

“This group is sometimes called ‘opt-out mothers,’ although some researchers say they may have been pushed out of the workforce due to work-family conflicts,” Pew says. “In 2012, nearly 370,000 U.S. married stay-at-home mothers (with working husbands) had at least a master’s degree and family income exceeding $75,000.”

And let’s be clear — this is their choice.

“A companion public opinion survey by Pew, from 2013, found that mothers are much more likely than fathers to have reduced work hours, take a significant amount of time off, quit a job or, by a small margin, turn down a promotion in order to care for a child or family member,” Pew says.

Forty-two percent of mothers said they had reduced their work hours to care for a child or family member, versus 28 percent of fathers.”

In other words, American women appear to be pretty traditional in their life choices.

What does this mean for the women’s movement? While the public square is all atwitter with talk of “leaning in” and balancing work with home life, a significant portion of American women just aren’t listening.

That fact takes nothing away from women who choose to work, or who have to work.

But it does put the “women’s movement” in a different light.