Last quarter, more homeowners voluntarily defaulted on their mortgages and chose to walk away from their homes than the total number of mortgages permanently modified to date under the Administration's year-old Home Affordable Modification Program (HAMP). According to new data from the team of researchers at the University of Chicago and Northwestern University that first identified the scope of "strategic default" behavior last year, the number of homeowners willing to default when the value of a mortgage exceeds the value of their house, even if they can afford to pay their mortgage, has dramatically increased compared to just a year ago.