by Calculated Risk on 4/22/2008 07:26:00 PM

Roger Lowenstein writes in the New York Times Magazine: Triple-A Failure (hat tip Jasper and others). This is an excellent overview of how the rating agencies failed. Here is an excerpt:

Moody’s recently was willing to walk me through an actual mortgage-backed security step by step. I was led down a carpeted hallway to a well-appointed conference room to meet with three specialists in mortgage-backed paper. Moody’s was fair-minded in choosing an example; the case they showed me, which they masked with the name “Subprime XYZ,” was a pool of 2,393 mortgages with a total face value of $430 million.

Subprime XYZ typified the exuberance of the age. All the mortgages in the pool were subprime — that is, they had been extended to borrowers with checkered credit histories. In an earlier era, such people would have been restricted from borrowing more than 75 percent or so of the value of their homes, but during the great bubble, no such limits applied.

Moody’s did not have access to the individual loan files, much less did it communicate with the borrowers or try to verify the information they provided in their loan applications. “We aren’t loan officers,” Claire Robinson, a 20-year veteran who is in charge of asset-backed finance for Moody’s, told me. “Our expertise is as statisticians on an aggregate basis. We want to know, of 1,000 individuals, based on historical performance, what percent will pay their loans?”

The loans in Subprime XYZ were issued in early spring 2006 — what would turn out to be the peak of the boom.

Lowenstein follows XYZ through the rating process, and through the eventual downgrades.

Almost immediately, the team noticed a problem. Usually, people who finance a home stay current on their payments for at least a while. But a sliver of folks in XYZ fell behind within 90 days of signing their papers. After six months, an alarming 6 percent of the mortgages were seriously delinquent. (Historically, it is rare for more than 1 percent of mortgages at that stage to be delinquent.)

Moody’s monitors began to make inquiries with the lender and were shocked by what they heard. Some properties lacked sod or landscaping, and keys remained in the mailbox; the buyers had never moved in. The implication was that people had bought homes on spec: as the housing market turned, the buyers walked.

By the spring of 2007, 13 percent of Subprime XYZ was delinquent — and it was worsening by the month.

Shocked? Homebuyer's were speculating with no money down. Mortgage brokers didn't care because they would sell the loans immediately and collect their fees. Wall Street didn't care because they could package the loans and sell them to investors. Investors would have cared, except they trusted the rating agencies. And as this article describes, the rating agencies weren't evaluating the underlying loans - they were performing statistical analysis using models based on lenders that cared if the borrower would repay the loan.

At the same time, regulators - despite numerous warnings - mostly ignored the problem, apparently for ideological reasons ("let the free market work"). What a mess.