California remains the top source of new single-family mortgages for Fannie Mae and Freddie Mac, even as Fannie remains the dominant GSE in terms of production through the first half of the year, according to an Inside The GSEs analysis. A total of $56.9 billion in home loans on Golden State properties were securitized by the two GSEs during the first six months of 2014, accounting for 21.0 percent of their total business for the half year.