Despite significant corporate turmoil and an historic regulatory settlement, Fannie Mae has quietly begun to win back some of the share of the government-sponsored enterprise market that it had lost to rival Freddie Mac in 2005. According to the Inside Mortgage Finance MBS Database, Fannie Mae issued a total of $229.4 billion of single-family mortgage-backed securities during the first half of this year. That total, which includes only pass-through pools, was up 8.8 percent from… [Three data tables included]