WASHINGTON — The recession has hit middle-income and poor families hardest, widening the economic gap between the richest and poorest Americans as rippling job layoffs ravaged household budgets.

The wealthiest 10 percent of Americans — those making more than $138,000 each year — earned 11.4 times the roughly $12,000 made by those living near or below the poverty line last year, according to newly released census figures. That ratio was an increase from 11.2 in 2007 and the previous high of 11.22 in 2003.

Household income declined across all groups, but at sharper percentage levels for middle-income and poor Americans. Median income fell last year from $52,163 to $50,303, wiping out a decades worth of gains to hit the lowest level since 1997.

Poverty jumped sharply to 13.2 percent, an 11-year high.

"No one should be surprised at the increased disparity," said Richard Freeman, a Harvard University economist. "Unemployment hurts normal workers who do not have the golden parachutes the folks at the top have."

Analysts attributed the widening gap to the wave of layoffs in the economic downturn that has devastated household budgets.

While reductions in executive pay might have hit the richest Americans, those at the bottom of the income ladder are often unemployed and struggling to get by, they say.

Large cities such as Atlanta, Washington, New York, San Francisco, Miami and Chicago had the most inequality, largely because of years of middle-class flight to the suburbs. Declining industrial cities with pockets of well-off neighborhoods, such as Pittsburgh, Cleveland and Buffalo, also had sharp disparities.

Up-and-coming cities with growing middle-class populations, such as Mesa, Ariz.; Riverside, Calif.; Arlington, Texas; and Henderson, Nev., were among the areas showing the least income differences between rich and poor.

Whether income inequality will continue to worsen in major cities remains unclear, said William H. Frey, a demographer at the Brookings Institution. Many Americans are staying put for now in traditional cities to look for jobs and because of frozen lines of credit.

"During the years of the housing bubble, there was middle-class movement from unaffordable metros with high-income inequality," Frey said. "Now that the bubble burst, more of the population may be headed back to the high-inequality areas, stemming their middle-class losses."

As for poverty, the biggest shifts last year were increases in metropolitan areas in Florida and central California. The poverty rated jumped to 16.8 percent from 14.1 percent in Stockton, Calif., and to 15.4 percent from 12.7 percent Lakeland- Winter Haven, Fla. The proportion of poor people also increased in Tampa-St. Petersburg, Orlando, Bradenton and Palm Bay — all in Florida.

Among other findings:

Income for the top 5 percent of households — those making $180,000 or more — was 3.58 times the median income, the highest since 2006.

Twenty-one states and the District of Columbia had higher poverty rates than the national average. Many are in the South, such as Mississippi, at 21.2 percent, and Kentucky, Arkansas and Louisiana, each with 17.3 percent. In 2007, the poverty rates in 19 states and the District of Columbia exceeded the national average.

Use of food stamps jumped 13 percent last year to nearly 9.8 million households.