(Bloomberg News) The number of Americans living in neighborhoods beset by extreme poverty surged in the last decade, erasing the progress of the 1990s, with the poorest areas growing more than twice as fast in suburbs as in cities.

At least 2.2 million more Americans, a 33 percent jump since 2000, live in neighborhoods where the poverty rate is 40 percent or higher, according to a study released today by the Washington-based Brookings Institution.

The report, which analyzed Census Bureau data, shows the extent to which the U.S. lost ground in efforts to fight poverty during a decade marked by recessions, including the deepest slump in seven decades. The Midwest and South were hardest hit, suffering from manufacturing job losses and the housing bust.

"With two downturns and a decade that saw the typical household income fall, the 2000s took an economic toll," said Elizabeth Kneebone, a senior research associate at the Brookings Metropolitan Policy Program and lead author of the report.

When people are concentrated in very poor neighborhoods, they face a host of additional problems from worse schools and fewer job opportunities to poor health, she said.

The report follows the release of data by the Census Bureau in September that showed the number of people living in poverty was the highest in the 52 years since the agency began gathering the statistic. U.S. household income fell to its lowest level in more than a decade in 2010 and poverty rose to a 17-year high.

Economic hardship and joblessness will be the focus of next year's presidential campaign and these statistics will help fuel debates in Congress and in statehouses across the U.S. over budget cuts to programs designed to help families in need.

The Brookings study shows that areas of concentrated poverty soared by more than a third in the past decade after declining by 29 percent during the 1990s. The rise in the number of people living in these neighborhoods compares with a 28 percent drop in the '90s.

While more than two-thirds of extremely poor neighborhoods remain in urban areas such as Chicago and Detroit, the number of Americans in extremely poor suburban neighborhoods rose by 37 percent between 2000 and the second half of the decade, more than two times faster than the 16 percent growth in cities.

"The days of thinking about poverty as being an urban phenomenon are over," said Scott Allard, associate professor at the University of Chicago's School of Social Service Administration and the author of the book, "Out of Reach: Place, Poverty and the New American Welfare State."