Greater Des Moines foreclosure rates dropped to less than 1 percent of all mortgages in November, real estate analytics firm CoreLogic Inc. said in a release. Foreclosures dropped to 0.99 percent in November, down from nearly 1.8 percent a year ago. The national foreclosure rate was about 1.5 percent in November. The mortgage delinquency rate also decreased, dropping to 2.8 percent from 3.7 percent a year ago. The delinquency rate reflects mortgages that are at least 90 days overdue.