The nonprime mortgages held in portfolio by the government-sponsored enterprises continued to decline in 2017, according to an analysis by Inside Nonconforming Markets. And while the GSEs sold vintage non-agency mortgage-backed securities during the year, pre-crisis Alt A mortgages guaranteed by Fannie Mae and Freddie Mac are largely running off instead of being sold. Fannie and Freddie had a total of $108.23 billion in nonprime mortgage holdings ... [Includes one data chart]