The percentage delinquent mortgages held by Fannie Mae and Freddie Mac continued the fall experienced in nearly every month this year. The 30-plus day delinquent mortgage rate on Fannie Mae’s book fell to 4.7% in August, the latest month of available data, down 12 basis points from the previous month, according to its monthly summary. For Fannie, it’s the sixth straight month of declines. Freddie Mac’s 90-plus day delinquency rate reached 3.8% in September, down 3 basis points from the previous month, according to its summary. It’s the fourth straight month of declines for Freddie and would have been the seventh were it not for a singular, unchanged rate in May at 4.06%. But from a year ago, delinquency rates for both government-sponsored enterprises remain elevated. Fannie’s delinquency rate is still up 25 bps from 4.45% in August 2009. The Freddie delinquency rate is 37 bps from the 3.43% reported in September 2009. Credit Suisse analysts estimate the total losses at Fannie and Freddie will eventually reach $321 billion. If home prices drop further from their estimate and delinquencies and foreclosure mount again, that number could reach as high as $448 billion. Write to Jon Prior.