Bad credit was the number one reason that many would-be mortgage borrowers were turned away, recently released Home Mortgage Disclosure Act data show. Overall, problem credit accounted for 37.4 percent of conventional home-purchase loan rejections last year, down slightly from 40.4 percent in 1999, the HMDA data show. The story was pretty much the same for every racial group last year. Credit history was the main factor in 49.6 percent of purchase-money rejections among African