The serious delinquency rate on single-family mortgages held by Fannie Mae was 4.56% in September, a 16 basis point drop from September 2009 and the first yearly decline since April 2007. In April 2007, the serious delinquency rate was at 0.62%, down 2 bps from April 2006. The September 2010 rate, the latest available from Fannie Mae, also marked the seventh-straight monthly decline. It was down 14 bps from August. The last time the delinquency rate increased from the previous month was in February, when it climbed 7 bps to 5.59%. It has averaged a roughly 14 bps drop every month since to what is now its lowest point since August 2009. Fannie Mae mortgage-backed securities issuance held flat in October at $69.6 billion, roughly the same as the previous month but up roughly 71% from a year ago. So far in 2010, Fannie Mae has issued $472.6 billion in MBS. In 2009, Fannie issued $807.8 billion. The Fannie Mae gross mortgage portfolio declined in October to $798.2 billion, down 0.5% from the previous month but up 3.5% from a year ago. Write to Jon Prior.