For love or money? The number of unmarried couples living together is rising sharply as many young adults who are having a hard time finding jobs are now "doubling up" with significant others.

The number of opposite-sex unmarried couples who shared living arrangements jumped 13 percent this year to 7.5 million, the Census Bureau reported Thursday. That's compared to a 2 percent decrease between 2008 and 2009.

There were about 620,000 same-sex couples living together, a figure not statistically different from a 2008 census estimate of 565,000.

Demographers say a sluggish job market is the likely factor. Many young adults turned first to friends and parents for financial help since the recession began in late 2007, and may now be leaning on boyfriends or girlfriends as unemployment benefits and savings accounts dwindle in the prolonged economic downturn.

"It would be odd to say this year was emotionally different, so it's more likely practical considerations that are behind the increase in cohabitation," said Rose Kreider, a family demographer at the Census Bureau who reviewed the numbers.

Her analysis, published Thursday in a 19-page census working paper previewing the 2010 data, shows that newly formed unmarried couples living together were more likely to have one partner unemployed, who was often male. They also typically lived in the South where poverty was more widespread and sometimes in larger households, such as with parents or other couples.

Among the cohabitation findings:

—Thirty-eight percent of newly formed unmarried couples lived in the South, compared to 23.2 percent in the West, 23 percent in the Midwest and 15.8 percent in the Northeast.

—Thirty-seven percent of men in newly formed unmarried couples living together were ages 15 to 29, compared with 23 percent of the men in already existing unmarried couples. For women, 45 percent in the new couples were 15 to 29, compared to 32 percent in existing relationships.

—Fifty-seven percent of the newly formed unmarried couples were made up of two non-Hispanic white people, compared to 68 percent among existing unmarried couples.

The 2010 numbers come from the Census Bureau's Current Population Survey, an annual survey taken in March by a sample of U.S. households. They are not a part of 2010 decennial census figures which will be released beginning in December.

The findings come after the Census Bureau reported last week that the U.S. poverty rate jumped in 2009 to 14.3 percent, or 43.6 million people, the highest since 1994. Additional 2009 data being released next week will also highlight the impact of the Great Recession on everyday life.