While proprietors suffer in a depressed housing market, one group is doing very well: mortgage fraudsters. According to a new report from the Lexis Nexis Mortgage Asset Research Institute, fraud and misrepresentation in the mortgage market reached record proportions in 2010, costing an estimated $1.5 billion.

All told, the number of mortgage fraud “suspicious activity reports” rose to 70,472 nationwide, a 5 percent increase over 2009. Most of those reports concerned misrepresentation on loan applications and verifications of deposit, as well as appraisal and valuation issues. Florida, New York and California topped the institute’s Mortgage Fraud Index, which measures instances of fraud against new mortgage originations.

Also in the top 10: New Jersey, Maryland, Michigan, Virgina, Ohio, Colorado and Illinois.