The number of Americans living in multi-generational households grew more than five times as sharply as the overall population increased from 2007 to 2009, the years that spanned the Great Recession, this according to a report released by the Pew Research Center. The largest increase was among adults ages 25 to 34 who live with their parents.

In 2009, a record 51.4 million Americans lived in a multi-generational household. These households included one-in-six Americans (16.7 percent) and more than one-in-five adults ages 25 to 34.

The population living in households with more than three family...