New business at the Federal Home Loan Mortgage Corp. retreated to its lowest level in six months. Delinquency, meanwhile, remained at its lowest level in a decade.

When September was over, Freddie Mac’s total mortgage portfolio stood at $2.1513 trillion — including a $0.2278 trillion in mortgage investments and $1.9235 trillion in outstanding mortgage-related securities and other guarantees.

The McLean, Virginia-based company revealed the metrics in its Monthly Volume Summary, which indicated that the book of business had expanded from $2.1472 trillion a month earlier and $2.0568 trillion a year earlier.

Purchases and issuances came to $31.296 billion last month — the slowest month since March. Volume was $38.413 billion in August and $35.297 billion in September 2017. For the first nine months of this year, purchases and issuances amounted to $285.600 billion.

At 0.73 percent, single-family 90-day delinquency remained at
the lowest level it’s been since January 2008. Serious mortgage delinquency at the government-controlled company was 0.86 percent as of Sept. 30, 2017.

Multifamily delinquency of at least 60 days was unchanged at 0.01 percent and was down from 0.02 percent in the same month last year.