THE BACKGROUND
Auto lenders collect less information on borrowers than mortgage lenders do-dealers want buyers driving off lots that day, after all-and are issuing loans to more consumers with credit scores below 620 (gener-ally, the definition of subprime). As they do with mortgage- backed securities, investors rely on credit-ratings firms to put their stamps of approval on bonds backed by car loans-a market valued at $178.2 billion as of Sept. 30. Investors don't usually receive specifics about the underlying debt, as they now do with home-loan bonds.