Freddie Mac's issuance of MBS totaled $57.7 billion in March nearly double its activity in February as a result of the surge in refinancings.
The mortgage giant purchased $52 billion in refinanced mortgages in March, its largest refinance purchase month since 2003.
The company also said it added $45.1 billion in mortgage assets to its investment portfolio, including $19.1 billion of its own MBS. And the mortgage investment portfolio grew to $867.1 billion as of March 31.
Meanwhile, delinquencies continue to creep up. In March, the percentage of Freddie single-family loans that are 90 days or more past due or in foreclosure rose to 2.29%, up 16 basis points from the previous month, and up from 0.77% in March of 2008.
In other Freddie Mac news, former chief executive David Moffett is returning to Freddie Mac to run the finance division in the wake of the apparent suicide of the company's acting chief financial officer David Kellermann.
Freddie interim chief executive John Koskinen welcomed Moffett's offer to temporarily return as a consultant while Freddie searches for a permanent CFO.
"He knows the company well from his time as the chief executive, and has built an impressive career in finance and accounting...with other leading public companies," Koskinen said.