Who are you? What have you become? Throughout our lives, we are enmeshed in a network of social relationships that influence us, for better or for worse. Most of our relationships have some value to us, else we would not be in them. They constitute social capital—a form of wealth every bit as valuable as financial or human capital.
Family relationships are the first a person experiences in life. Children are nurtured, taught, and socialized in the family, and from there learn to relate to others and participate in the broader society. A stable family offers the emotional security a child needs for healthy development. As Princeton University sociologist Sara McLanahan has noted:
“If we were asked to design a system for making sure that children’s basic needs were met, we would probably come up with something quite similar to the two-parent ideal. Such a design, in theory, would not only ensure that children had access to the time and money of two adults, it also would provide a system of checks and balances that promoted quality parenting. The fact that both parents have a biological connection to the child would increase the likelihood that the parents would identify with the child and be willing to sacrifice for that child, and it would reduce the likelihood that either parent would abuse the child.”

As sources of valuable social capital, few relationships are as important as the family ties between parents and children. However, as with other features of our associational life, family ties have been weakening for several decades. Today, around 45% of American children spend some time without a biological parent by late adolescence that is up from around one-third of children born in the 1960s and one-fifth to one-quarter born in the 1950s. Even more strikingly, among the most disadvantaged socioeconomic groups, even fewer children are raised in continuously intact families. Single parenthood is experienced by two-thirds of the children of mothers with less than a high school education and by 80% of black children. This inequality in family stability contributes to but also compounds economic inequality.

Intact Families and Opportunity

Researchers have well established that children raised by married parents do better on a wide array of outcomes. They have stronger relationships with their parents, particularly with their fathers. They are also much less likely to experience physical, emotional or sexual abuse. They have better health, exhibit less aggression, are less likely to engage in delinquent behaviour, have greater educational achievement, and earn more as adults. They are also far less likely to live in poverty.
Rigorously establishing the causal importance of family structure is far from straightforward, however. Few studies are up to the task. And among the most rigorous studies, about half find the estimated effects of experiencing single parenthood are not large enough to reliably say they are real rather than artifacts of imprecise statistical methods. It is surely the case that many children are harmed by family disruption. But other people raised by single parents may have had worse outcomes if their parents had married or stayed married. People raised by two happily married parents would almost surely have done worse if their family had been disrupted. But the alternative for people who were raised by single parents would not necessarily have been being raised by two happily married parents.
A second paper, from Austrian researchers, considered whether experiencing a parental divorce affects a range of outcomes. They isolated impacts on children who would have been raised by both their parents if not for the fact that their fathers’ workplaces had relatively high numbers of women similar in age to the father and working in the same occupation. That is, these children experienced divorce because their fathers were more likely to enter into an extramarital affair simply by virtue of circumstances that make an affair more likely. The study found that experiencing divorce worsened educational, employment, and health outcomes for this subset of children. Again, the results make sense: many of these children may have been in what seemed to them to be fairly healthy families, and the divorces they experienced were likely to have involved a great deal of acrimony and pain.

Family Stability Has Declined

However, American families are far less stable today than in the past. Fewer Americans are married, more romantic relationships take place outside of marriage, more marriages end in divorce, and ultimately, more children are born into or raised outside of intact families.
Although most Americans still marry or say they would like to marry, marriage is not nearly as common as it was in previous generations. Overall, between 1962 and 2019, the percentage of women ages 15-44 who were married dropped from 71% to 42% (Figure 1). Furthermore, Figure 2 shows the percentage of women ages 30-34 who had never married increased from 7% in 1962 to 35% in 2019.
In 1960, there were 74 marriages per 1,000 unmarried women ages 15 and older, but as of 2018 that rate had declined by more than half to 31 per thousand. People spend less of their life married, as the median age at first marriage in the United States has steadily climbed from 20 and 23 for women and men, respectively, in 1960 to a median of 28 and 30, respectively, in 2019 (Figure 3).
The decline in marriage is due not only to increasingly delayed marriage and to the rise in never-married adults, but also to higher divorce rates. In 1960, the divorce rate was 9 per 1,000 married women, and that rate increased through the 1960s and 1970s, reaching 23 per 1,000 1980. Comparable estimates are surprisingly difficult to obtain after 1980, but by 2010 the divorce rate probably was somewhat lower (21 per 1,000), and it fell further to 17 per 1,000 by 2018. 21 Any post-1980 drop was confined to the under-35 population.. (In the past decade, divorce has also fallen among those in their late thirties and early forties, but the rate remains elevated relative to 1980.).

Furthermore, the overall divorce rate after 1980 may have declined only because the Baby Boomers aged out of the part of the life cycle where divorce is most common. When Sheela Kennedy and Stephen Ruggles considered what would have happened had the population not aged between 1980 and 2010, they found that divorce rates would have risen about as much between 1990 and 2010 as between 1970 and 1980.
Because divorce rates have fallen during the part of the life cycle when divorce is most common, it may be that today’s post-Millennials, when they are the age of today’s Baby Boomers, will be less likely than Boomers to have divorced at some point in their lives (conditional on having been married). Kennedy and Ruggles estimated that ever-married Americans in their 20s or early 30s in 2010 were less likely to have divorced than their same-age counterparts in 1980. However, as noted, their marriages will likely be at greater risk for divorce when they are older than used to be the case. (Divorce rates among older women increased between 1980 and 2010 then stabilized.).
As marriage has declined, couples have become more likely to cohabit as unmarried couples. In the 1960s, less than one percentage of couples living together were unmarried—a figure that rose to 5% by 1990 and stood at 12-13% as of 2019 (Figure 5).. Furthermore, marriage is much more likely to be preceded by cohabitation today than in the past. Among women ages 19 to 44 who married between 1965 and 1974, just 11% had cohabited with their husbands prior to marriage, but that number jumped to 32% among those who married between 1975 and 1979 and continued to soar thereafter. For the past two decades, two-thirds of new marriages have been preceded by cohabitation.

The decline in marriage and the increase in cohabitation has led to substantial growth in unwed childbearing. The percentage of births to unmarried mothers has jumped from 5% in 1960 to 40% today. That is only slightly below the peak of 41% in 2009. This increase in unwed births is due not only to the decline in marriage overall, but also to the decline in “shotgun marriages” or post-conception/pre-delivery marriages, as we show in a previous report. In the early 1960s, births produced by nonmarital conceptions followed a shotgun marriage 43% of the time, but today fewer than 10% involve a shotgun marriage. In fact, besides the decline in marriage rates overall, which increased the pool of women “at risk” for an unwed birth, the decline in shotgun marriage has been the largest contributing factor to the rise in unwed births. It has been the single most important factor contributing to rising unwed childbearing among women under thirty.
While unmarried mothers are often cohabiting with the father of their child at the time of the child’s birth, cohabiting relationships are far less stable than marriages. In a 2007 study researchers found that 50% of children born to cohabiting parents experienced a maternal partnership transition by their third birthday, compared to just 13% of children in married-parent families. Thus, children born into households where the parents are not married are much more likely to see their parents break up.
The combination of unwed births and divorce has led to a marked rise in the share of children living with a single parent. Fifty years ago, in 1970, 85% of children lived with two parents, 4% of children lived with a divorced single parent, while another one percentage lived with a never-married parent. (The rest lived with only one married parent present, had a widowed parent, or lived with neither parent.)
Family instability in the United States has also led to an increase in the percentage of Americans who have children with multiple partners, creating complicated relationships across households. Nearly 16% of all parents in the United States have children with more than one partner, and in 20% of all marital or cohabiting relationships, at least one of the partners has children with more than one partner. Furthermore, fathers with multi-partner fertility are less likely to say they feel close to their children and are more likely to have failed to establish paternity for at least one of their children .
Although family instability has increased among all Americans, family instability is far more common among the non-college-educated. The highly educated marry more often, stay married more often, and rarely bear children outside of marriage. (We define highly-educated as being in roughly the highest quintile of educational attainment, low education as being in roughly the lowest quintile of educational attainment, and moderate education as those in the remaining quintiles.

Family stability also varies by race

As of 2019, 57% of highly-educated women ages 15-44 were married, compared to only 36% of moderately-educated women and 18% of women with low education. These differences were much smaller in the mid-1960s, with less than ten percentage points separating the three groups in 1964.
Unfortunately, family instability has increased to the point where it is the norm for many Americans today. Troublingly, those most likely to experience family disconnection are the least-advantaged among us. While family instability does not necessarily doom a child to poorer life outcomes, it often means greater disconnection in the most intimate of human relationships and less social capital of the strongest type.