Of four in 10 households with children under the age of 18, mothers are the sole or primary provider.


That's according to new analysis from Pew Research Center using data from the U.S. Census Bureau. The number is up from 11 percent in 1960.

So-called "breadwinner moms" are made up of two groups: 5.1 million, or 37 percent, are married mothers who have a higher income than their husbands, while 8.6 million are single moms.

The income gap between the two groups is quite large as well.

Of the married mothers who earn more than their husbands, the median total family income was nearly $80,000 in 2011, which was nearly four times the $23,000 median for families led by a single mother. The growth in the trend is tied to women's increasing presence in the workplace. Women make up almost half of the U.S. labor force today, or 47 percent.

"I think this study reflects the changing roles that women have in our current environment. There have been major changes in family structure since 1960," said Maury Randall, Chairman of the Finance Department at Rider University.

"Many more women are now holding college degrees and this is providing opportunities to them for better paying jobs than they may have had in earlier years. Secondly, men were harder hit by the recent recession, especially in the manufacturing and construction sectors. We also have lower marriage rates and higher divorce rates, which has resulted in more single mothers. As a result, they are the ones providing the family income."

How does the public feel about the trend?

A majority of Americans, 79 percent, reject the idea that women should return to their traditional roles, according to the study. But, 51 percent say that children are better off if a mother is home and doesn't hold a job. When it comes to single mothers, 64 percent of respondents say the growing trend is a big problem. But, the share who feel this way is down from 71 percent in 2007.

Other key findings:

  • Both groups of breadwinner mothers, married and single, have grown in size in the past five decades. Of all households with children younger than 18, the share of married mothers who out-earn their husbands has gone up from 4% in 1960 to 15% in 2011, nearly a fourfold increase. During the same period, the share of families led by a single mother has more than tripled (from 7% to 25%).
  • The total family income is higher when the mother, not the father, is the primary breadwinner. In 2011, the median family income was nearly $80,000 for couples in which wife is the primary breadwinner, about $2,000 more than it was for couples in which husband is the primary breadwinner, and $10,000 more than for couples in which spouses' income is the same.
  • Married mothers are increasingly better educated than their husbands. Even though a majority of spouses have a similar educational background, the share of couples in which the mother has attained a higher education than her spouse has gone up from 7% in 1960 to 23% in 2011. In two-parent families today, 61% have a mother whose education level is similar to her husband's, 23% have a mother who is better educated than her husband, and 16% have a father who is better educated than his wife.
  • Most people reject the idea that it is bad for a marriage if a wife out-earns her husband. When asked if they agree or disagree that it is generally better for a marriage if a husband earns more than his wife, some 28% of survey respondents say they agree and 63% disagree. When a similar question was asked in 1997, 40% said they agreed. In the new survey, adults with a high school diploma or less were twice as likely as those with a college degree (35% vs. 18%) to say it is generally better for a marriage if a husband out-earns a wife. There were no significant differences between men and women on this question.
  • Today's single mothers are much more likely to be never married than were single mothers in the past. The share of never married mothers among all single mothers has increased from 4% in 1960 to 44% in 2011. During the same period, the share of single mothers who had children from previous marriages has gone down from 82% to 50%.
  • Never married mothers have a distinctive profile. Compared with single mothers who are divorced, widowed or separated, never married mothers are significantly younger, disproportionally non-white, and have lower education and income. Close to half of never married mothers in 2011 (46%) are ages 30 and younger, six-in-ten are either black (40%) or Hispanic (24%), and nearly half (49%) have a high school education or less. Their median family income was $17, 400 in 2011, the lowest among all families with children.