Freddie Mac (FRE) reported Thursday that its total mortgage portfolio shrank at the annualized rate of 8.1% in April, and its commitments to buy mortgage bonds dropped sharply to $956 million during the company.

The company added that much of its resources went toward purchase of refinanced loans under the Making Home Affordable program.

In a monthly report released Thursday, Freddie said it expects refinancing volumes to stay up in the near term as more homeowners take advantage of this opportunity to lower their mortgage rates and monthly payments.

Meanwhile, the mortgage company curtailed its mortgage bond commitments to $956 million from $15.8 billion in March. This was the first time Freddie had dropped these commitments to such a low number since last July..

Also, its single-family delinquency rate continued to go up under the dual impact of its foreclosure program being suspended and the broader economic slowdown.

Freddie said its delinquency rate rose to 2.44% in April from 2.29% in March.

Freddie noted that these numbers may be slightly skewed due to the temporary moratorium on its foreclosure program, which means loans stay delinquent instead of moving on to foreclosure. The company didn't reveal the extent of the impact.

Even then, these delinquency rates continue to rise to record highs for the mortgage finance giant, and are an indication of the extent of decline among prime borrowers with conforming loans. The delinquency rate was at 0.65% at the end of 2007.

Meanwhile, in March, Freddie's total investment portfolio was at $830.3 billion, down from $867.1 billion last month.

Over the past couple of months, the role of Freddie and its sibling Fannie Mae (FNM) have diminished in the mortgage market as both the U.S. Treasury and the Federal Reserve have emerged as backstop buyers with deep pockets.

However, market participants still keep tabs on Fannie and Freddie's portfolios as an indication of their financial health, and their ability to continue to play a role as both guarantors and buyers of mortgage bonds.

Other details in the monthly report show that Freddie's issuance of guaranteed securities and pass-through certificates dropped to $51 billion from $57.7 billion in March.

The mortgage giant's total mortgage portfolio shrank 8.1% in April to $2.231 trillion.

The duration gap, a measure of the portfolio's sensitivity to interest rates, averaged zero in April.

-By Prabha Natarajan, Dow Jones Newswires, 201-938-5071; prabha.natarajan@dowjones.com