For the first time, the percentage of women marrying a man with a lesser education is greater than the percentage of men marrying a woman with a lesser education. 

According to a new survey by the Pew Research Center, the gap -- 21% vs. 20-- is expected to widen.  Among newlyweds alone, the figures are 27% vs. 15%.

In 1960, only about 7% of women fell into this category, but the number has risen steadily over the years as women have surpassed men in college graduation rates.

Pew emphasizes that the phrase "marrying down" refers only to education, not economics. In fact, most women (58%) who had more education than their husbands in 2012 actually earned less money.