In keeping with its goal of shrinking the government-sponsored enterprise's role in the mortgage finance space, Fannie Mae saw its total book of business decline at an annualized rate of 8% in April.

Last month, the company's gross mortgage portfolio fell to $683.1 billion from $691.7 billion in March and is down from $746.8 billion a year earlier. Overall, its mortgage portfolio decreased at a compound annualized rate of 13.8%.

Fannie, meanwhile, finalized 12,552 loan modifications in April and 59,223 in the four-month period ending on April 30, 2012.

The conventional single-family serious delinquency rate dropped four-basis points to 3.63% in April, while the multifamily serious delinquency rate dropped two-basis points to 0.35%.

The GSE had $2.7 trillion in mortgage-backed securities and other guarantees in April. That is relatively stable from March and up slightly from $2.698 trillion last year.