In the next few weeks, debt-rating services like Moody's Investors Service, Standard & Poor's and Fitch Ratings look poised to downgrade hundreds of mortgage-related investments worth tens of billions of dollars, creating the potential for more market unrest.
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Credit-rating firms have lowered their credit ratings on more than $70 billion in mortgage-related bonds in the past few months, setting off waves of distress in the stock and bond markets. They've also expressed concerns about the outlook for a range of related industries from banking to bond insurance. Banks and Wall Street firms including Citigroup Inc. and Merrill Lynch & Co. took large charges when they were forced to reassess the value of even their highest-rated mortgage debt.
The article also has this very revealing graphic about the breadth of the writedowns:
This is going to get really ugly and confusing for money managers over the next year or so as they figure out what they can and can't invest in.