Greater Des Moines foreclosure rates decreased in February over the same period last year, according to real estate analytics firm CoreLogic Inc. The rate of foreclosures among outstanding mortgages was 2.3 percent, down from 2.65 percent in February 2012. The national foreclosure rate was 2.85 percent in February. The delinquency rate also dropped in Greater Des Moines, to 4.23 percent from 4.7 percent a year ago.