Mortgage giant Freddie Mae is finding itself on the downward side of the delinquency arrow – and when it comes to delinquencies, the downside is an angle the GSE didn’t see for a long three-year stretch.

According to Freddie’s monthly summary report released Tuesday, the company’s single-family delinquency rate fell to 4.06 percent in April, down 7 basis points from March. It was the second straight month that the GSE has

reported a decline in delinquencies. Its last report also showed a monthly drop of 7 basis points to 4.13 percent in March.

Up until that point, the McLean, Virginia-based GSE’s delinquency rate had been riding a steady incline since April 2007.

Freddie Mac’s refinance-loan purchase and guarantee volume was $18.4 billion in April, down from $23.1 billion in March.

However, Freddie’s total mortgage portfolio increased at an annualized rate of 3.0 percent in April, after shrinking in previous months. The aggregate unpaid principal balance (UPB) of the company’s mortgage-related investments portfolio grew by approximately $3.9 billion.

The GSE explained that the jump was due to its purchases of 120-plus day delinquent mortgages from securities pools, a move announced by both Freddie and Fannie Mae in early February as a result of new accounting rules, which require lenders to account for certain securitized assets on their own books.