and, in the half decade that followed, the value of Moody's shares improved by more than 300%. Structured finance boom and after Structured finance went from 28% of Moody's revenue in 1998 to almost 50% in 2007, and "accounted for pretty much all of Moody's growth" during that time. According to the Financial Crisis Inquiry Report, during the years 2005, 2006, and 2007, rating of structured finance products such as mortgage-backed securities made up close to half of Moody's rating revenues. From 2000 to 2007, revenues from rating structured financial instruments increased more than fourfold. However, there was some question about the models Moody's used to give structured products high ratings. In June 2005, shortly before the subprime mortgage crisis, Moody's updated its approach for estimating default correlation of non-prime/nontraditional mortgages involved in structured financial products like mortgage-backed securities and Collateralized debt obligations. Its new model was based on trends from the previous 20 years, during which time housing prices had been rising, mortgage delinquencies very low, and nontraditional mortgage products a very small niche of the market. On July 10, 2007, in "an unprecedented move", Moody's downgraded 399 subprime mortgage-backed securities that had been issued the year before. Three months later, it downgraded another 2506 tranches ($33.4 billion). By the end of the crisis, Moody's downgraded 83% of all the 2006 Aaa mortgage backed security tranches and all of the Baa tranches. In June 2013, Moody's Investor Service has warned that Thailand's credit rating may be damaged due to an increasingly costly rice-pledging scheme which lost 200 billion baht ($6.5 billion) in 2011–2012. Controversies Sovereign downgrades Moody's, along with the other major credit rating agencies, is often the subject of criticism from countries whose public debt is downgraded, generally claiming increased cost of borrowing as a result of the downgrade. Examples of sovereign debt downgrades that attracted significant media attention at the time include Australia in the 1980s, Canada and Japan in the 1990s, Thailand during the 1997 Asian financial crisis, and Portugal in 2011 following the European sovereign debt crisis. Unsolicited ratings Moody's has occasionally faced litigation from entities whose bonds it has rated on an unsolicited basis, and investigations concerning such unsolicited ratings. In October 1995, the school district of Jefferson County, Colorado sued Moody's, claiming the unsolicited assignment of a "negative outlook" to a 1993 bond issue was based on Jefferson County having selected S&P and