The Nikkei 225 (JPN225), commonly referred to as "The Nikkei" is a Japanese stock market index based on the market capitalization of the top 225 companies traded on the Tokyo Stock Exchange (TSE). This is a price-weighted index based on the Yen, and the value has been calculated daily by the Nihon Keizai Shimbun (Nikkei) newspaper since the Index's inception in 1950. The Nikkei 225 index got its start on September 7, 1950 and was retroactively calculated back to May 16, 1949. Nikkei 225 Futures Contracts got their start on the Singapore Exchange (SGX) in 1986 and then began trading in the United States when they debuted on the Chicago Mercantile Exchange (CME) in 1990. The Nikkei is the most widely quoted index when referring to Japanese equities, followed by the Topix which seeks to track all 1,669 companies listed on the first section of the Tokyo Stock Exchange (TSE).