The economy has relied on capital inflows to fund private-sector excess, with Turkey's banks and big firms borrowing heavily, often in foreign currency. Under these conditions, Turkey must find about $200 billion a year to fund its wide current account deficit and maturing debt, always at risk of inflows drying up, having gross foreign currency reserves of just $85 billion. Turkey has been meeting the “60 percent EU Maastricht criteria” for public debt stock since 2004. Similarly, from 2002 to 2011, the budget deficit decreased from more than 10 percent to less than 3 percent, which is one of the EU Maastricht criteria for the budget balance. In January 2010, International credit rating agency Moody's Investors Service upgraded Turkey's rating one notch. In 2012, credit ratings agency Fitch upgraded Turkey's credit rating to investment grade after an 18-year gap, followed by a ratings upgrade by credit ratings agency Moody's Investors Service in May 2013, as the service lifted Turkey's government bond ratings to the lowest investment grade, Moody's first investment-grade rating for Turkey in two decades and the service stated in its official statement that the nation's "recent and expected future improvements in key economic and public finance metrics" was the basis for the ratings boost. In March 2018, Moody's downgraded Turkey's sovereign debt into junk status, warning of an erosion of checks and balances under Recep Tayyip Erdoğan. In May 2018, credit ratings agency Standard & Poor's cut Turkey's debt rating further into junk territory, citing widening concern about the outlook for inflation amid a sell-off in the Turkish lira currency. Share prices in Turkey nearly doubled over the course of 2009. On May 10, 2017, the Borsa Istanbul (BIST) 100 Index, the benchmark index of Turkey's stock market, set a new record high at 95,735 points. As of January 5, 2018, the Index reached 116,638 points. However, in the course of the 2018 Turkish currency and debt crisis, the index dipped back below 100.000 in May. In early June, the BIST-100 dropped to the lowest level in dollar terms since the global financial crisis in 2008. In 2017, the OECD expected Turkey to be one of the fastest growing economies among OECD members during 2015-2025, with an annual average growth rate of 4.9 percent. In May 2018, Moody's Investors Service lowered its estimate for growth of the Turkish economy in 2018 from 4 percent to 2.5 percent and in 2019 from 3.5 percent to 2 percent.