Fannie Mae and Freddie Mac in 2012 combined for the third biggest year ever in single-family mortgage-backed securities issuance, according to a new Inside Mortgage Finance market analysis and ranking. Together, the two government-sponsored enterprises pumped out a whopping $1.266 trillion in new single-family MBS last year, a 48.2 percent increase over their total production back in 2011. It marked the biggest annual output by the two GSEs since they set the all-time record of $1.912 trillion back in 2003. Last year’s total came up just short of the second biggest annual issuance on record – $1.270 trillion – set in 2002. Heavy refinance activity was...[Includes three data charts]