In 2008, a study group established by the Committee on the Global Financial System (CGFS), a committee of the Bank for International Settlements, found that rating agencies had underestimated the severity of the subprime mortgage crisis, as had "many market participants". According to the CGFS, significant contributing factors included "limited historical data" and an underestimation of "originator risk" factors. The CGFS also found that agency ratings should "support, not replace, investor due diligence" and that agencies should provide "better information on the key risk factors" of structured finance ratings. In October 2007, Moody's further refined its criteria for originators, "with loss expectations increasing significantly from the highest to the lowest tier". In May 2008, Moody's proposed adding "volatility scores and loss sensitivities" to its existing rankings. Although the rating agencies were criticized for "technical failings and inadequate resources", the FSB stated that the agencies' "need to repair their reputation was seen as a powerful force" for change. Moody's has in fact lost market share in certain sectors due to its tightened rating standards on some asset-backed securities, for example the commercial mortgage-backed securities (CMBS) market in 2007.