USA Today reports that new Census data released this week suggest that 6.4 million opposite sex couples live together (as of 2007), up from less than one million thirty years ago. This means that cohabiting couples now make up nearly 10% of all opposite sex couples, including those who are married. 

In comparison, the Census bureau reported 5 million unmarried, opposite-sex households in 2006, but that figure was based on a question that many respondents found to be unclear. In the 2007 supplemental survey sample of 100,000 households, the Census questions asked more directly whether respondents had “a boyfriend/girlfriend or partner in the household” and found 1.1 million more couples.

The USA Today article included comments from two sociologists:

Pamela Smock,. a sociologist at the Population Studies Center at the University of Michigan at Ann Arbor who studies cohabitation, says the new data gets closer to the truth, but because it’s a point-in-time survey, it still misses the extent of cohabitation in today’s society.

“It’s a snapshot,” she says. “It’s not telling you how many people have ever cohabited, which is much more than that.” …

Sociologist Linda Waite of the University of Chicago, who has done extensive research into marriage and cohabitation, says living together in the USA isn’t very stable or long-term, compared to some Scandinavian countries where it’s more likely to be a long-term committed relationship.

But in the USA, she says, it’s become “part of the life course.” “It’s something people do that leads to somewhere,” she says. “If it doesn’t lead to marriage, it leads to splitsville.”

The full story.