The turmoil of the mortgage market granted a temporary reprieve from hearing about the woes of America's Rust Belt. That doesn't mean things are better. Despite a decade of national prosperity, the former manufacturing backbone of the U.S. is in rougher shape than ever, still searching for some way to replace its long-stilled smokestacks.

Where's it worst? Ohio, according to our analysis, which racked up four of the 10 cities on our list: Youngstown, Canton, Dayton and Cleveland. The runner-up is Michigan, with two cities--Detroit and Flint--making the ranking.

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These, and four other metropolitan statistical areas, as defined by the U.S. Census Bureau, face fleeing populations, painful waves of unemployment and barely growing economies. By our measure, they've struggled the worst of any areas in the nation in the 21st century. And they face even bleaker futures.

It wasn't always this way. Despite years of economic decline, in the first years of the new century the employment situation did not look so bad--3% to 4% unemployment was the norm, along the lines of metropolitan areas elsewhere in the country. The rest of the decade was not so kind. Thanks to a crushing downturn for automakers like General Motors and Ford, Detroit and Flint, Mich., have seen unemployment approach 10%.

Another brutal statistic all the cities share is a diminishing population. So far this decade, 115,000 people have left Cleveland, for other climes. Smaller changes in other regions can be just as painful. Nearly 30,000 people have left Youngstown, Ohio, and they aren't being replaced by either new babies or new immigrants.

Still, the cities we found to be struggling don't vary widely by age, and this factor had little influence in the rankings. The oldest city in our top 10, Scranton, Pa., had 45% of its population over 45; the youngest, Flint had 38% over 45.

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The worst news is, of course, economic. When we looked at the most recent gross domestic product estimates for 155 metropolitan statistical areas estimated to have $10 billion or more GDP in 2005--economies about the size of Asheville, N.C., or Tallahassee, Fla.--the news was predictably terrible for the Rust Belt.

In the fall of 2007, the U.S. Bureau of Economic Analysis (BEA) published its GDP estimates from 2001 to 2005. Nearly every city in the country grew during this period (New Orleans, devastated from Hurricane Katrina, was the notable exception), but the struggling cities on our list grew more sluggishly. None of them grew more than 1.9% a year, versus a nationwide average of 2.7%. Canton, Ohio, managed to grow its economy just 0.7% annually. Flint was worse still at 0.4%.

None of these cities now face the huge declines in real estate prices seen by Phoenix, Miami or Las Vegas, where the Case-Shiller Home Price Index shows nearly 30% declines from a year ago. Detroit is off only about 15%, Cleveland only 8%. Don't call it a bright spot. Prices never went up in the first place.

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