A quarter of 40-year-old Americans have never been married, more than in any other time since data has been collected, according to a new analysis of Census data by Pew Research. The trend is more pronounced among African Americans, 46% of whom reach 40 without marrying, and those with who do not have a degree, a third of whom remain unwed by that age. And more of them are male; 28% of 40-year-old men have never married, versus 22% of women the same age.

In some ways the figures are unsurprising; there has been a four-decades-long trend away from marriage since it peaked in the middle of the 20th century. In 1980, only 6% of 40-year-olds had never been married. That increased five percentage points per decade until 2021, the year from which Pew drew its data.

But in other ways, the news is remarkable, since it reflects not just a turn away from the institution of marriage, but a rejection of the idea of pair-bonding. Just one-in-five of unmarried 40- to 44-year-olds are living with a romantic partner. Cohabitation is not replacing marriage as a living arrangement.

There are many reasons partnering up is losing ground in America. Some of them are societal; there is very little public stigma around being single—for many, it’s the preferred option. Some are cultural; the way households are formed is being refashioned by questions of gender and sexuality. Some are technological; as sex was decoupled from pregnancy, sexual habits changed and so did the need for marriage or a partner.

But perhaps the most salient ones are economic. It’s not just that as women gained economic power, they needed to rely less on men to provide. It’s that many of the economic forces of the last 30 years, including globalization and digital technology, have crushed the earning opportunities of young men. “As an economist, I think some of the trends, particularly for less educated young men, are working against them,” says Richard Fry, a senior researcher at Pew, who wrote the analysis. “Economically, they’re not as attractive partners as they once were. The nation’s labor market is working against them.”

One way in which this becomes clear is in the difference between the trend lines for marriage and wages between men and women since the 1990s. Single men’s median income, adjusted for inflation, has fallen in the last 30 years. Single women’s has remained unchanged. As men fell down the economic ladder, they also became more likely to remain single than women. “In 1990, there were more unpartnered women than there were unpartnered men,” adds Fry. “By 2019, that reversed.”

Surveys show that women still seek a partner who is a provider, but it seems to also be true that men don’t feel ready for marriage if they’re not prospering. Bridgette Reed, a marriage and family therapist in Dallas, sees these forces playing out in the community she serves. “Most Black men feel they need a certain level of financial stability to be married,” she says. “When they feel the weight of financial pressure, getting married is last on their list.”

Education is also becoming increasingly highly correlated with marriage. Only 18% of people with a bachelor’s degree are single at the age of 40. In 1990, women with a degree were less likely to be married than those without. By 2021, that had reversed.

How many of these 40-year-olds will go on to marry? If history is a guide, says Fry, about 20%. Marriage advocates are alarmed by the figures. “We’ve never been in this family territory before, territory where so many young adults have never tied the knot,” says Brad Wilcox, director of the National Marriage Project at the University of Virginia. “The reason this matters is that men and women are much more likely to be flourishing financially, socially, and emotionally when they are married rather than single.”

Read More: Men are Now More Likely Than Women to Be Single

Fry points to Census and American Community Survey figures on householders who are 40 and older. “In the most recent data, the typical married household has a wealth of about $360,000 and the typical non-married household has a wealth of about $97,000.” While it’s unclear whether marriage makes people richer or richer people marry—or both—the net effect is that single people may enter their retirement years with less wealth.

They also may have less family to support them. About 46% of never-married 40-year old women and 20% of the men have their own children in their household. “We have a growing number of older adults who are both childless and never married,” says Fry. “Now we’re starting to get into older ages. And you start to think about support issues: who’s going to take care of them as they proceed into their relatively older age?”

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