Of the 52 million U.S. homeowners with a mortgage, more than a quarter -- nearly 14 million -- are underwater. They owe more on their mortgage than their home is worth. The Homeowner Affordability and Stability Plan, announced by President Barack Obama on Feb. 18, is intended to help some of these families stay in their home.

The first group to get help is homeowners whose mortgage is higher than the value of their home and who have been keeping up with their monthly payment. They would like to refinance to today's lower interest rates but can't do this because banks won't let homeowners refinance if they have little or no equity in their home.