The Treasury may try to bring new mortgage rates down to 4.5%—a full percentage point lower than current rates—to revitalize the housing market, the Wall Street Journal reports. Under the proposal, which is still in the early stages, the department would use Fannie Mae and Freddie Mac to lower the rates. The idea comes after months of struggling to hatch a plan to reduce foreclosures and stem falling prices without directly bailing out borrowers and lenders. (More subprime crisis stories.)