California remained the biggest source of new single-family mortgages for Fannie Mae and Freddie Mac during 2011, according to the new special report, GSE Market Profile: 2011, from Inside Mortgage Finance Publications.A total of $189.9 billion of home loans on California properties were securitized by the two GSEs, accounting for 22.6 percent of their total business for the year. That was down 15.1 percent from the total California Fannie/Freddie production back in 2010, while the overall GSE market fell 17.0 percent from a year ago.Although fixed-rate mortgages dominated the GSE market in 2011, California produced $17.9 billion in adjustable-rate mortgages – 30.8 percent of the national total. ARMs accounted for just 6.9 percent of the total GSE volume.