Nationwide, employment among young adults 16-29 stood at 55.3 percent, down from 67.3 percent in 2000 and the lowest since the end of World War II.
Also a rebound in the foreign-born population to 40 million, or 12.9 percent, the highest share since 1920.
Most immigrants continue to be low-skilled workers from Latin America, with growing numbers from Asia also arriving on the bet that U.S. jobs await. An estimated 11.2 million immigrants are here illegally.
In all, the employment-to-population ratio for all age groups from 2007-2010 dropped faster than for any similar period since the government began tracking the data in 1948.
In the past year, 43 of the 50 largest U.S. metropolitan areas continued to post declines in employment, led by Charlotte, N.C., Jacksonville, Fla., Las Vegas, Phoenix, Los Angeles and Detroit, all cities experiencing a severe housing bust, budget deficits or meltdowns in industries such as banking or manufacturing.
About 1 in 4 families with children is headed by single mothers, a record high.
Among young families with a head of household younger than 30, the poverty rate jumped from 30 percent in 2007 to 37 percent.
In contrast, poverty remained at a low 5.7 percent for families with a head of household 65 or older
The number of households receiving food stamps swelled by 2 million to 13.6 million, meaning that nearly 1 in 8 receives the government aid.
The highest shares of recipients are in Oregon, Tennessee, Michigan, Kentucky and Mississippi. Among households receiving food stamps, more than half have children.