The thinnest city in America needs to fatten up to keep its professional sports franchises.

Denver is the most overextended market for professional sports in North America. Research done by the Business Journals has the Mile High City at the top of a list of 20 markets that are lacking enough income to support their existing major league sports teams.

Known as the "Baby Boomer" capital of America, the Rocky Mountain town is lacking cash.

The home of the Broncos, Rockies, Nuggets, Avalance and Colorado Rapids has a total personal income of $121.9 billion. Research shows Denver needs a total personal income of $209.3 billion to properly provide a proper base for its five existing teams. That $87.4 billion income deficit is by far the biggest of any market.

While it's not good news, the report says it doesn't mean any of the Denver area teams will move, but the shortfall is a sign of attendance and revenue problems for years to come.

Top 10 Overextended Markets For Pro Sports

City (deficit in billions of dollars)
1. Denver ($87.4)
2. Cleveland ($71.4)
3. Pittsburgh ($56.6)
4. Tampa Bay ($54.1)
5. Kansas City ($52.2)
6. Milwaukee ($51.8)
7. St. Louis ($42.2)
8. Phoenix ($41.0)
9. Minneapolis ($39.4)
10. Cincinnati ($37.5)

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