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Updated at 12:50 p.m. ET on April 8, 2019.

In 2018, happiness among young adults in America fell to a record low. The share of adults ages 18 to 34 reporting that they were“very happy” in life fell to 25 percent—the lowest level that the General Social Survey, a key barometer of American social life, has ever recorded for that population. Happiness fell most among young men—with only 22 percent of young men (and 28 percent of young women) reporting that they were “very happy” in 2018.

We wondered whether this trend was rooted in distinct shifts in young adults’ social ties—including what The Atlantic has called “the sex recession,” that is, a marked decline in sexual activity for this group in recent years. Human beings find meaning, direction, and purpose in and through our social relationships with others. We’re happiest when our ties with others are deep and strong. And the research tells us that the ebb and flow of happiness in America is clearly linked to the quality and character of our social ties—including our friendships, community ties, and marriage. It’s also linked, specifically, to the frequency with which we have sex. In the antiseptic language of two economists who study happiness, “sexual activity enters strongly positively in happiness equations.”

So we investigated four indicators of sociability among today’s young adults—marriage, friendship, religious attendance, and sex—in an effort to explain the “happiness recession” among today’s young adults.

First, we looked at marriage. Controlling for basic demographics and other social characteristics, married young adults are about 75 percent more likely to report that they are very happy, compared with their peers who are not married, according to our analysis of the GSS, a nationally representative survey conducted by NORC at the University of Chicago. As it turns out, the share of young adults who are married has fallen from 59 percent in 1972 to 28 percent in 2018. The decline has been similar for men and women, although from 2016 to 2018 the share of married men fell, while the share of married women rose.

Data on cohabitation are not available for as long a period, but suggest that the trend in all coupling is probably less steeply negative, though still drifting downward over time. Less coupling, then, probably explains some of the decline in happiness among young adults.

Faith was the second factor. Young adults who attend religious services more than once a month are about 40 percent more likely to report that they are very happy, compared with their peers who are not religious at all, according to our analysis of the GSS. (People with very infrequent religious attendance are even less happy than never-attenders; in terms of happiness, a little religion is worse than none.) What’s happening to religious attendance among young adults today? The share of young adults who attend religious services more than monthly has fallen from 38 percent in 1972 to 27 percent in 2018, even as the share who never attend has risen rapidly. Among young men, nonattendance is much more common than regular attendance, and the gap is steadily growing. Less involvement in the life of a local church, mosque, temple, or synagogue, we speculate, might translate into less happiness for young adults.

The third factor was friendship. The effect of seeing friends frequently is less clear than that of marriage or religion, but young adults who see their friends regularly do seem to be about 10 percent more likely to report being very happy than their less-sociable peers. Friendship among young adults, though, is not on the decline; in fact, since 2006, contact with friends is up. Lack of friendship, then, is not likely to play a role in declining levels of happiness. Indeed, it may be that rising social time spent with friends in recent years could be buffering young adults from the declines in institutions such as marriage or religion, as friends stand in place of other relationships or forms of community.*

And, finally, we looked at sex. Young adults who have sex at least once a week are about 35 percent more likely to report that they are very happy, compared with their peers who have no sex. But the share of young adults having sex at least once a week has fallen from 59 percent in 1972 to 49 percent in 2018. This decline is far steeper among men: down from 58 percent of young men having sex at least weekly in 2010 to just 43 percent in 2018. And the share of young adults reporting no sex in the past year has risen as well, now at 22 percent for young men and 14 percent for young women in 2018.

This trend in rising sexlessness is broadly confirmed in other surveys of sexual behavior, including the National Survey of Family Growth, the National Health and Nutrition Examination Survey, and the Youth Risk Behavior Surveys. Less sex, we speculate, could help account for declining happiness for many young adults.

To assess which of these factors might matter most, we built counterfactual models that show what the path of happiness might have been had one or two variables been different. We allowed the happiness trends within a given group, such as “people who attend religious services 2-3 times per month” to follow their actual, historic paths, but for 2010 to 2018, we fixed each group’s population share to 2008 levels. This let us answer the question, “If happiness trends within demographic groups were the same, but the composition of the population across groups had not changed, what would happiness be today?” We conducted this exercise separately for population composition broken out by religiosity, sexual frequency, marital status, and contact with friends, to see how big of an effect changes in behaviors across these four metrics of sociability might have mattered.

This analysis revealed that changes in sexual frequency can account for about one-third of the decline in happiness since 2012 and almost 100 percent of the decline in happiness since 2014. If Americans still had sex like they did in 2008, or even 2012, we might be a much happier country. Declines in marriage and religiosity have also played some role, but the effects are much smaller—with each factor only accounting for about a tenth of the decline in happiness. And, but for the rise in regular friend contact over the past few years, young men and women would be even less happy.

In other words, Americans are offsetting some of the lost community and companionship of spouses and churches with closer ties to friends. But those friendships don’t give young Americans the sex life that made previous generations happier.

Clearly, the United States is in the middle of a “sex recession.” Nowhere has this sex recession proved more consequential than among young adults, especially young men. Some academics and journalists have now begun grumbling about what they are calling a “moral panic” about the decline in young-adult sex. Before the 2018 data came out, the Daily suggested that the decline in sex was modest, and the sociologist Daniel Carlson claimed that the amount of sex one has “is a weak predictor of how satisfied you are with your sex life.” More important than frequency, the argument went, is the quality of your sexual relationship.

What’s more, as the #MeToo era has taught us, there has been too much unwanted or nonconsensual sex out there, which is obviously bad for the (more often female) target of such advances. From this perspective, the so-called sex recession might just amount to a sexual recalibration, with a lot of bad sex being eliminated from our social lives—and this would be a good thing. For all these reasons, the feminist family historian Stephanie Coontz is “suspicious of any hand-wringing” about the sex recession.

But the significant and ongoing rise in sexlessness still gives us pause, both because it appears to be making some Americans appreciably less happy, and because it may be an indicator of the trouble facing young adults when it comes to love and marriage. Indeed, while marriage composition independently has only a modest effect on society-wide happiness, the decline in sexual frequency is itself related to postponed marriage: Married people have sex more often. Finding a spouse can be hard and, crucially, one of the places young adults have historically found their spouses is church. Thus, while most of the decline in happiness is about declining sex, that’s not the end of the story. Declining sex is at least partly about family and religious changes that make it harder for people to achieve stable, coupled life at a young age. If we’d like more young adults to experience the joy of sex, we will have to either revive these institutions or find new ways to kindle love in the rising generation.


* This article originally misrepresented the share of men regularly spending an evening with friends in Figure 5, which shows increased contact with friends among 18-34-year-olds.

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