(CBS News) A newly released government report finds the state of marriage in the U.S. is fragile: The percentage of people living together has nearly quadrupled over the last three decades and nearly 50 percent of marriages end within 20 years, according to the Centers for Disease Control and Prevention.
So is marriage becoming obsolete?
That's not the case, according to Dr. Andrew Cherlin, a sociologist at Johns Hopkins University and author of "The Marriage-Go-Round: The State of Marriage and the Family in America Today."
The report shows people are taking longer to marry, but they're eventually getting around to it, Cherlin said. By the time people are 40 years old, he explained, most people do get married, but it happens these days in their late 20s or 30s.
"What's happened is the place of marriage in our lives has changed," he said. "(It) used to be that marriage was the first step into adulthood. You got married, then you got a job, then you got apartment. Now it's often the last step, when everything else is done, when your personal life is in order, you celebrate by getting married."
As for the statistic of many marriages ending after 20 years, Cherlin said it's the flip-side of "the great American individualism."
"We're concerned about ourselves, our personal development," he said. "We see marriage in a very personal way. We value it, but if it's not successful in providing us with what we need, we feel justified in leaving it."
The U.S., Cherlin noted, has the highest divorce rate of any wealthy country in the world.
But why is that?
Cherlin said it's because we're American. "We think we're justified in having the best personal life we can do," he said. "We move on to new relationships if the first one isn't well."
For more with Cherlin on marriage, watch the video in the player above.