Foreclosure rates in Des Moines-West Des Moines dropped to 1 percent of active mortgages in December, down 0.75 percentage points from the same period last year, real estate analytics firm CoreLogic Inc. said in a release. Foreclosure activity was lower than the national foreclosure rate, which was 1.47 percent for December 2014.The mortgage delinquency rate also declined in the metro area, with 2.7 percent of mortgages at least 90 days delinquent, compared with nearly 3.6 percent the same time last year.