Drawing from decades of data on people getting married for the first time (or not), sociologists Daniel Schneider, Kristen Harknett, and Matthew Stimpson confirmed what we already knew: In the U.S., is on the rocks and has been for about a half-century. What they did to move the conversation forward, in their article in the Journal of , was to try to explain why.

Marriage scholars have some long-standing favorite explanations for why people marry. For men, it is all about “marriageability.” Men are considered marriageable if they have a “threshold level of economic resources.” When men’s economic fortunes fall, marriage rates will fall, too. The growing rates of incarceration undermine men’s resources and could also contribute to the decline of marriage.

The theoretical counterpart to the “marriageable man” is the “independent woman.” Over the past half-century, more and more women have been working in the paid workforce, and the gap between their pay and men’s has been decreasing. If women have more money and more , does that mean that they are less likely to marry? The answer to that question, it turns out, has changed over time.

Using these standard ways of thinking about how to live a life, the authors found some partial answers. I’ll describe their findings next. Most important, I think, is what they — and the generations of marriage researchers who came before them — are missing. I’ll end with some of my thoughts about why fewer people are marrying than ever before.

How the Study Was Done

The authors analyzed data from more than 18,000 people who were interviewed between the ages of 15 and 50 when they were not yet married. The data came from the Panel Survey of Income Dynamics, 1969—2013. The survey was longitudinal, meaning that the same people participated in the study year after year. On average, each person stayed in the study for seven years.

In addition to keeping track of who got married, the authors also measured key factors such as income, employment, incarceration, and education. Analyses focused primarily on non-Hispanic Blacks and Whites, because there were relatively few Hispanics or people of other ethnicities in the study.

What They Found

In the 45 years between 1969 and 2013, the scholars found, marriage rates plummeted.

Among men: For those who had a high school education or just some college, the decline of marriage was sharper than for those with a bachelor’s degree.

For those who had a high school education or just some college, the decline of marriage was sharper than for those with a bachelor’s degree. Among women: Those with at least a bachelor’s degree went from being the least likely to marry in 1969 to the most likely to marry in 2013.

Men’s declining economic resources were important. Part of the answer to the question of why fewer people have been marrying over the past half-century is that men have less work, and the income they are earning from work is decreasing. These factors, though, only explain about one-third of the decades-long decline of marriage among men.

Incarceration has increased greatly over the past decades, and that contributed to the decreasing rates of marriage, too. But not a huge amount. For Black men, for example, having been incarcerated explains only 8 percent of their decreasing likelihood of marrying.

The story is different for women. Their work opportunities have increased over the past decades. But in recent years, women with more resources are more likely to marry. That means that the economic and educational fortunes of women cannot explain the decline of marriage. Women today are doing better than they used to, and the women who are doing especially well economically are more likely to marry.

In sum, the sociologists learned a little about why marriage rates are decreasing by looking at men’s changing economic fortunes and rising rates of incarceration. They learned nothing about why fewer people are marrying by looking at women’s improving economic and educational status.

Clearly, they are missing something — probably lots of things, including big things — by focusing only on the tired old ways of thinking about how to live a life.

Only when they got to the middle of the last paragraph of the last page of their article did they float a different way of thinking:

"…research on family changes has often invoked the decline in the "normative imperative to marry" and the rise of the acceptability of alternative family forms as explanations . . . It is possible that the changing normative context played some role in the decline in first marriage rates during this period."

That’s it: two sentences. Then the authors went right back to discussing economic factors and incarceration in their final sentence.

So what are they missing? I’m not picking on them. They were following the lead of the scores of marriage researchers who came before them. They are all missing out on other ways of thinking about the decline of marriage and the rise of single life.

The Missing Reasons for the Decline of Marriage

I. Marriage is not necessary the way it once was.

Decades ago, people often waited (or tried to wait) until marrying before having kids, having , or buying a home. Now those possibilities are readily available outside of marriage.

1. Children

Want children? No need to marry.

It used to be considered shameful to have children outside of marriage. Today, single parents and their children still get some side-eye, but attitudes are more enlightened than they once were.

Plus, if you are raising kids, and you are not married, you have record numbers of other people to keep you company. One out of every four parents (25 percent) is unmarried, compared to just 7 percent in 1968.

Your kids have company, too. There are now 24 million children living with a parent who is not married (compared to 9 million in 1968). Percentage-wise, that’s 32 percent now, compared to 13 percent then. And that’s just counting the kids currently living with an unmarried parent. Plenty more had that experience in the past or will have it in the future.

Your kids also have rights. That may seem self-evident now, but before the 1968 Levy v. Louisiana Supreme Court ruling, the children of single parents were considered officially “illegitimate” and had fewer rights than the children of married parents.

There’s also the matter of the logistics of having kids when you don’t have a husband or any man. That, too, was more daunting a half-century ago than it is now. There has been lots of progress in reproductive medicine, with more innovations sure to come.

Worried that your kids are doomed if they are not being raised by married parents? That scare story has been vastly overblown.

2. Sex

Sex outside of marriage is something else that used to be considered shameful. Now, with our sex-obsessed culture, if you are single, it almost seems more shameful not to be having sex than to be having it.

Sex has also become more available to people outside of marriage for another reason: birth control. Women can now have sex with far less chance of becoming . The pill gets a lot of the credit for that — and it was not approved until 1960. (Even then, single women were excluded at first.) Accessibility of abortion is relevant, too.

3. A House

Want a home of your own, complete with real furniture and adorned in your own style? Young adults used to wait until they married to do that. Not anymore.

II. There are many positive reasons why people choose to live single.

1. They don’t want to put one particular person at the center of their life, or the one person they care about most is not a romantic partner.

The model of adult life that puts one romantic partner at the center is just one way to live a life. Some people care most about another person who is not a romantic partner. Others have a number of friends and relatives who are important to them; often they value the flexibility of deciding when they want to see those people, rather than feeling obligated to be with them most of the time. Still others like to spend most of their time alone.

2. They love solitude.

More people than ever before are choosing to live alone. Solitude comes with deep rewards for those who value it. Counterintuitively, people who live alone are in many ways more connected to other people than those who live with others. They get their own space and meaningful social ties, too.

3. They want to pursue their passions.

Some single people want to put their passions at the center of their life. Those passions could include meaningful work, the pursuit of social justice, creative work, pursuits, travel, and much more.

4. They want to create the life that works best for them, and that life does not include marriage.

People with the resources to do so have more opportunities than ever before to create a fulfilling life outside of marriage. I can’t wait to see the possibilities people come up with as more and more of them realize that there is no marriage imperative anymore. That was so last century.

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