The number of shared households dips

Haya El Nasser, USA TODAY | USATODAY

The share of adults living under someone else's roof has declined for the first time since the recession began in 2007 — a hint that the economy is improving.

The number and percentage of households where adults are doubling up climbed four years in a row and peaked in 2010 at 22.2 million (19.4%). It dipped to 22 million (19.2%) in 2011, according to a Census report released Wednesday. The figures cover homes shared by adults who are not spouses or partners.

We think it's economics that's driving this," says Suzanne Macartney, co-author of the Census report. "In states with higher poverty rates, we find more shared households."

Many of the adults living under one roof would have been in poverty had they lived on their own, the Census Bureau reported.

Doubling up, which has become increasingly common mostly for young adults and seniors, declined in eight states in 2011.

"It looks like we bottomed out, and this is one of many recent indicators that shows this," says William Frey, demographer at the Brookings Institution.

Living in someone else's home is a more common way of life in high-immigration states such as California, Texas, Florida, New York and New Jersey. That may be due to cultural preferences. Many immigrants come from countries accustomed to several generations under one roof.

And more adults are doubling up in states that have high housing costs or high rates of foreclosures. At least 20% of the adults in California, Florida, Hawaii, New York, Nevada and the District of Columbia are sharing a home.

Other highlights:

--More than a third of 18- to-24-year-olds and more than one in four ages 25 to 34 lived under someone else's roof last year. The increase since 2007 was greater in the older young adults group. The Census did not include young adults 18-24 who were enrolled in school.

--In California, Florida, Hawaii, Maryland, New Jersey and New York, more than a third of adults ages 25 to 34 lived in someone else's home. "That's not the college-age group but the post-college group,'' Macartney says.

It's an age group that may be feeling squeezed by housing costs, tough mortgage financing and a tight job market. "They're having trouble getting mortgages and they're having trouble getting jobs," Frey says. "That's still a spillover from the recession. They're hunkering down."

--The number of adult children living at home went up by 1.7 percentage points from 2007 to 2011 while the percentage of additional adults who were parents or non-relatives declined.

--Most adults living with others are not married.

--The number and percentage of adults living with others increased in 40 states since 2007. The largest increases were in Florida and Nevada.

--States facing the highest percentage of seniors living in someone else's home include Texas, California and Florida. "It's like the children moved to the Sun Belt and now they're making room for their parents," Frey says.