A new report from the Pew Research Center finds that total family income is around $2,000 higher when mothers are the primary breadwinners. The median income for households in which mom brings home the bacon is also $10,000 higher than when spouses make the same amount of money. According to data Pew obtained from the U.S. Census Bureau, 40% of homes with children in America feature mom as the primary or only source of income. That’s up from 11% in 1960.

The study also shows that mothers who are the primary or sole provider in the home can be split into two drastically different groups separated by a large income gap. 5.1 million (37%) are married mothers who have a higher income than their husband, while 8.6 million (63%) are single mothers. The median family income for the first group was nearly four times larger than that of the second.

Aside from income differences, there are also dramatic cultural differences between high-earning married mothers and single mothers. Higher-earning moms who are married and have kids under 18 tend to be older, white, college educated women. Lower-earning single mothers tend to be younger, African American or Hispanic, and less likely to hold a college degree.

The Pew report attributes the growth of breadwinner moms to the increasing presence of women in the workplace. Women make up 47% of the American labor force. A survey conducted by Pew finds that this trend has left American in two minds about mothers in the workplace. 74% of those surveyed say the increasing number of women working has made it more difficult for parents to raise children, and around 51% say it has hurt the chances of marriages to succeed. However, around 66% said having two working parents makes it easier for a family to live comfortably.

Other interesting findings of the Pew report:

- Total family income is higher when the mother, not the father, is the primary breadwinner.
- Married women are increasingly better educated than their husbands.
- Today’s single mothers are much more likely to never be married than were single mothers in the past.