According to an analysis by First American Core Logic, about 10 million US houses are worth less than their mortgages, as the result of the housing crisis.

After analyzing a huge data base of public records, First American Core Logic found that more than 7.5 million single-family homes have negative equity and another 2.1 million were very close to being upside down at the end of September.

The analyses of 42 million properties with mortgages, found the states with the highest percentage of upside-down mortgages were Nevada (48 percent), Michigan (39 percent), Florida (29 percent), Arizona (29 percent), California (27 percent), and Georgia (23 percent).

Those six states are home to about one in three US mortgages, but account for more than 58 percent of the nation's upside-down homes, First American CoreLogic estimated.

Take those six states out of the equation, and the percentage of US homes with a negative-equity mortgage is 12 percent, rather than 18 percent, the analysis found.

Some homeowners own their property outright and do not have a mortgage. However, add the 2.1 million mortgages that are within 5 percent of being upside down, and 23 percent of single-family homes with mortgages are upside down or near upside down, First American CoreLogic estimates.

Being upside down, -- owing more on a mortgage than a home would fetch in a sale -- does not necessarily mean a homeowner will end up in foreclosure.

SG/HAR