Fannie Mae announced Tuesday it began marketing its eighth re-performing loan sale as part of its ongoing effort to reduce its retained mortgage portfolio.

In its second quarter earnings release, the company explained the majority of its net income is now generated through guaranty fees as it continues to reduce its retained mortgage portfolio.

Re-performing loans are mortgages that were previously delinquent, but are performing again because payments on the mortgages have become current with or without the use of a loan modification.

This latest sale consists of about 18,400 loans with an unpaid principal balance of about $3.59 billion, and is available for purchase by qualified bidders.

The latest sale in re-performing loans is being marketed in collaboration with Citigroup Global Markets. All bids are due by September 6, 2018.

The terms of Fannie Mae’s re-performing loan sale require the buyer to offer loss mitigation options designed to be sustainable to any borrower who may re-default within five years following the closing of the re-performing loan sale.

In addition, buyers must report on loss mitigation outcomes. Any reporting requirements cease once a loan has been current for 12 consecutive months after the closing of the re-performing loan sale.