A common trope in America depicts a traditional family of a married husband and wife and their 2.5 (yes, 2.5) children as the norm, if not perhaps the ideal. Leaving aside the idea of a "traditional" coupling or what the right number of children might be, is there an advantage to growing up with married parents?

Definitely, argues Melissa Kearney, author of The Two-Parent Privilege: How Americans Stopped Getting Married and Started Falling Behind and the Neil Moskowitz Professor of Economics at the University of Maryland. In this Social Science Bites podcast, she reviews the long-term benefits of growing up in a two-parent household and details some of the reasons why such units have declined in the last four decades.

As befits her training, Kearney uses economics to analyze marriage. "Marriage," she tells host David Edmonds, "is fundamentally an economic contract between two individuals—here, I'm gonna sound very unromantic—but it really is about two people making a long-term commitment to pool resources and consume and produce things together."

In her own research, Kearney looks specifically at being legally married within the United States over the last 40 years and what that means when children are involved. Her findings both fascinate her and, she admits, worries her.

"We talk at length in this country about inequality as we should, but this divergence in family structure and access to two parents and all the resources that brings to kids and the benefits it gives kids in terms of having a leg up in sort of achieving things throughout their life—getting ahead economically, attaining higher levels of education—[well,] we will not close class gaps. without addressing this."

She provides data showing that the percentage of young Americans living with married parents is indeed falling. In 2020, 63 percent of U.S. children lived with married parents, compared to 77 percent 40 years earlier. Meanwhile, 40 percent of children are born to unmarried parents.

While these percentages are evenly distributed across the geography of the U.S., they are less so among the nation's demographics. For example, children born to white or Asian, more educated or richer mothers are more likely to be born within wedlock.

"The mechanical drivers of this," Kearney explains, "are a reduction in marriage and a reduction in the share of births being born inside of marital union, not a rise in divorce, not a rise in birth rates to young or teen moms." But economics does seem to be a driver, Kearney said – especially among men.

As cultural tumult saw marriage itself growing less popular starting in the 1960s, non-college-educated men saw their economic prospects dimming. "We saw a reduction in male earnings or a reduction in male employment and a corresponding reduction in marriage and rise in the share of kids born outside of marital union. So, there is a causal effect here, economic shocks that have widened inequality hurt the economic security of non-college educated men, and this rising college gap and family structure."

Over time, new social norms were established, so even when the economic prospects of non-college-educated men rise, there is not a corresponding increase in marriage and decrease in non-marital births. "Once a social norm has been established, where this insistence on sort of having and raising kids in a marital union is broken, then we get this response to economic shocks that we might not have gotten if the social norm towards two-parent households and married-parent households was tighter."

In addition to her work at the University of Maryland, Kearney maintains a large footprint in the policy world. She is director of the Aspen Economic Strategy Group; a research associate at the National Bureau of Economic Research; a non-resident senior fellow at Brookings; a scholar affiliate and member of the board of the Notre Dame Wilson-Sheehan Lab for Economic Opportunities; and a scholar affiliate of the MIT Abdul Jameel Poverty Action Lab, known as J-PAL.

So it's no surprise that she closes her interview with some policy suggestions.

"[I]mproving the economic position of non-college educated men, I think, is necessary but won't be sufficient. We need more wage subsidies. We need a lot of investment in community colleges throughout the country—they train workers throughout the country—we need to be shoring up those institutions. We need to be stopping bottlenecks in the workforce that make it harder for people without a four-year college degree, or for people who have criminal past, right, criminal history—all of those things. We need to be removing barriers to employment, investing in training, investing in skills, investing in paths to families to sustaining employment."