Declining refinance volume contributed to a marked decline in the GSEs’ overall business at the end of 2013 as Fannie Mae and Freddie Mac posted big declines in business on a quarterly and total 12-month basis, according to a new Inside The GSEs analysis. Fannie and Freddie issued $182.2 billion in new single-family mortgage-backed securities during the three-month period ending Dec. 31, 2013, a two-year low.