This isn’t too surprising considering the number of women getting college and graduate degrees today, but a new statistic puts those education figures in a different light: “almost 40 percent of U.S. working wives now out-earn their husbands.”

Reading Washington Post reporter Liza Mundy’s book, The Richer Sex: How the New Majority of Female Breadwinners Is Transforming Sex, Love and Family, out this March, was a genuine shock. Based on 2009 Bureau of Labor Statistics figures hot off the press (a government economist slipped Mundy the stats before they were published, in fact), “almost 40 percent of U.S. working wives now out-earn their husbands.” While that’s not the majority-grandiose subtitles definitely are the norm-it’s darn close to it. (For the record, my guess was 25 percent, the figure in the early ’90s.)

Luckily for my ego, Mundy tells me in an interview that she too was surprised at the 40 percent, and, better yet, she says, “Most of the expert readers I’ve given the manuscript to don’t believe it.” The lofty number of female breadwinners, or more accurately, female primary breadwinners, isn’t just a product of our devastating recession. As has been well publicized, largely male employment sectors such as manufacturing did contract the most during the recent economic downturn, accelerating the trend. But since way back in 1987, the slice of wives taking home more than their husbands has risen steadily, by a percentage point or so every year.

That’s principally because so many more women than men are getting undergraduate and postgrad degrees-by 2050, there will be 140 college-educated women in the U.S. for every 100 similar men-and because the economy is bifurcating between low-skill, low-wage jobs and high-skill, higher paying ones (that require a bachelor’s or more), with the middle emptying out.

Indeed, another title of Mundy’s book could’ve been The Big Flip. It’s the phrase she uses to denote the time not so far away-2025 is her hunch, based on her impressive research, which, in addition to a data dump, includes interviews with scores of ordinary people living the new reality-when more than half of the earners-in-chief in American households will be women. (Another factoid pointing toward the imminence of the flip: Nine out of the 10 U.S. job categories expected to grow most in the next decade-nursing, accounting, postsecondary teaching-are female dominated.)

While this is a weirdly casual account of these figures, the author is correct in suggesting this could lead to big changes in relationships and the established patriarchy.

One issue I haven’t seen raised when looking at data like this is while women may be making more money and be getting more degrees, will they really be in positions of power in society? While women may have relative power in the household (though having an economic edge doesn’t necessarily translate into more power), this doesn’t necessarily mean that these women have power in their workplace. You could end up with a situation where women’s status at home is up, which I think some would see as is a good thing, but they are still subordinates in male-led careers and workplaces, which would not be viewed as positively.