A Credit Suisse report released today said that Freddie Mac could report losses between $1 billion and $5 billion on its investment-grade subprime securities.

From Reuters:

"While Freddie's AAA subprime securities likely have substantial subordination, if the recent credit spread widening does not reverse over the coming quarters, we believe that Freddie could recognize an other-than-temporary impairment of between $1-5 billion," the brokerage said in a research note.

The losses may force Freddie to sell some of its portfolio holdings or raise capital by issuing preferred stock, the note added.

Freddie's shares fell nearly 8 percent today to close at $37.50, a new 52-week low.