Credit unions originated $31.4 billion in mortgages through the first half of 2010, down 43% from the $55.3 billion completed in the same time last year, according to data compiled for HousingWire from research firm Callahan & Associates. Credit unions are cooperative financial institutions controlled by its members. The latest total is also down more than 20% from the second half of 2009. According to the research, 82% of credit unions are now in the mortgage lending business. But these companies account for only 3.9% of the origination market share, down from 5.2% last year. "After a refi-fueled boom in 2009, first mortgage originations are back to historical average levels," according to Callahan & Associates. As a result, "sales to the secondary market have declined in tandem with the origination slowdowns." By the second quarter of 2010, credit unions sold $15.1 billion of mortgages to the secondary market, less than half of the $30.8 billion sold in the first half of last year. More than 42% of the $314.8 billion in credit union's real estate portfolio consist of first-mortgage fixed-rate loans. The rest is fairly evenly spread among various other fixed and adjustable-rate mortgages. The delinquency rate on the real estate portfolios reached 2.03% through the first half of 2010, up from roughly 1.5% last year. By comparison, the Federal Deposit Insurance Corp. (FDIC) reported more than $258 billion in loans on its insured institutions' balance sheets were more than 30 days delinquent. That's roughly 5.9% of the total loans backed by real estate those institutions hold. Write to Jon Prior.