Analysts who reviewed complex mortgage bonds that ultimately collapsed and ruined the U.S. housing market were threatened with firing if they lost lucrative business, prompting faulty ratings on trillions of dollars worth of junk mortgage bonds, a Senate report said [on April 13]. The 639-page report by the Senate Permanent Subcommittee on Investigations confirms much of what McClatchy Newspapers first reported about mismanagement by credit ratings agencies in 2009. Credit rating agencies are supposed to provide independent assessments on the quality of debt being issued by companies or governments. Traditionally, investments rated AAA had a probability of failure of less than 1 percent. But in collusion with Wall Street investment banks, the Senate report concludes, the top two ratings agencies - Moody's Investors Service and Standard & Poor's - effectively cashed in on the housing boom by ignoring mounting evidence of problems in the housing market. Profits at both companies soared, with revenues at market leader Moody's more than tripling in five years. Then the bottom fell out of the housing market, and Moody's stock lost 70 percent of its value; it has yet to fully recover. More than 90 percent of AAA ratings given in 2006 and 2007 to pools of mortgage-backed securities were downgraded to junk status.