Delinquencies on single-family loans guaranteed by Freddie Mac fell to 4.13 percent in March, down from 4.20 percent in February.

It’s the first monthly decline reported by the McLean, Virginia-based mortgage giant since April 2007, and some say a sign that efforts to improve loan performance are finally gaining ground.

“The decrease was driven by a higher volume of completed loan modifications as well as higher short sale volume during the month,” Michael Cosgrove, a spokesman for Freddie Mac, explained to Reuters.

The GSE’s multifamily delinquency rate also dropped slightly. In March, overdue multifamily mortgages were 0.24 percent, compared to 0.25 percent the month before.

The aggregate unpaid principal balance of Freddie Mac’s mortgage-related investments portfolio was $753.3 billion at the end of March, up from $732.2 billion in February.

The company explained that this growth was largely related to purchases of loans from mortgage-backed securities holders, which began in February, when the GSE announced that it would buy back more than $71 billion in delinquent loans from mortgage pools it had sold to investors.

Freddie Mac’s total mortgage portfolio decreased at an annualized rate of 9.1 percent in March.