SAN JOAQUIN COUNTY, Calif. -- A community in San Joaquin County Calif., has the highest amount of negative equity in the nation, according to a new report from First American CoreLogic.

The report shows that in the 95391 ZIP code, there's an 88.7 percent negative equity share, meaning that nearly 90 percent of the homeowners in Mountain House owe more on their homes than what the property is actually worth, Sacramento station KCRA reported.

The syndrome affecting those homeowners is known as being upside-down on mortgages.

The community's total property value is $639,544,348, but its total outstanding mortgage debt is $865,595,950 -- a loss of $226,051,602.

First American CoreLogic said California's total negative equity is 27 percent.

The ZIP code 95742 in Rancho Cordova is No. 4 on the list, with an 84.3 percent negative equity share.