Paul Taylor, co-author of the report, said 16.1 percent of U.S. residents, 49 million people, are currently living in homes containing multiple generations of family members, The Washington Post reported Friday.
"For some families, when you lose your home, you lose your job, what do you do? You go to your family," Taylor said. He said extended family represents "the ultimate social-safety net."
Taylor said the number of people living in multigenerational homes increased by 2.6 million, more than 5 percent, from 2007 to 2008, during the early stages of the recession.
The report also said 37 percent of 18- to 29-year-olds were unemployed or out of the workforce in 2009. The researchers said the figure represented a nearly four-decade high.