Some 23 percent of all U.S. residential properties with mortgages were in negative equity as of September 2009, according to a report from First American CoreLogic. Borrowers with negative equity, also described as "underwater" or "upside down," owe more on their mortgages than their homes are worth. In New York, 6.3 percent of residential properties with mortgages were in negative equity-a much lower rate than the national average. Other Northeast states had higher rates, including Massachusetts, where 15.6 percent of mortgaged residential properties were in negative equity at the end of September. Nevada had the nation’s highest negative equity rate at 65 percent.