Age at marriage: The conventional wisdom is that the later you marry, the more likely that the marriage will last. This idea stems more from elite rejection of the 1950s model of family life than it does the research. (Research shows that teen marriages are the ones at risk).
Getting married while young is now considered low-class. By contrast, a long stretch of lies, used people, broken hearts, STDs, unwanted pregnancies, and abortions is a sign of enlightenment.
Tens of thousands of Americans have been asked about their age and marriage and their current marital status by the General Social Survey. I divided people into groups based on age at marriage, and looked at marital statuses after at least 20 years had passed:
Percent in each category
Married in teens
Married between ages 20 and 24
Married between ages of 25 and 29
Married between the ages of 30 and 34
Married between the ages of 35 and 39
Married between the ages of 40 and 44
The benefit that is gained by waiting is gained by your early 20s. The chance of being divorced or separated is roughly the same for everyone else, and the rate of widowhood is higher for those who married late.
Many of those who married later had failed cohabitation experiences which would add to the rate of relationship failures if they were counted.
Which reminds me of another research finding that contradicts the modern attitude toward family formation: people who cohabit before marriage are more, not less, likely to get divorced.