In his final speech scheduled as Treasury secretary, Henry M. Paulson Jr. yesterday proposed replacing mortgage-finance companies Fannie Mae and Freddie Mac with highly regulated utilities that would play a more limited role in making money available for home loans.

Paulson, speaking at the Economic Club of Washington, explored ways to reshape the nation's housing finance system. With his tenure expiring, his opinions will carry little formal authority, but few officials have had as intimate a look at the two companies as Paulson.

Washington Post