Nikkei 225
Japanese stock market index
The Nikkei 225, or the Nikkei Stock Average (Japanese: 日経平均株価, Hepburn: Nikkei heikin kabuka), more commonly called the Nikkei or the Nikkei index (), is a stock market index for the Tokyo Stock Exchange (TSE). It is a price-weighted index, operating in the Japanese Yen (JP¥), and its components are reviewed twice a year. The Nikkei 225 measures the performance of 225 highly capitalised and liquid publicly owned companies in Japan from a wide array of industry sectors. Since 2017, the index is calculated every five seconds. It was originally launched by the Tokyo Stock Exchange in 1950, and was taken over by the Nihon Keizai Shimbun (The Nikkei) newspaper in 1970, when the Tokyo Exchange switched to the Tokyo Stock Price Index (TOPIX), which is weighed by market capitalisation rather than stock prices.
History
The Nikkei 225 began to be calculated on 7 September 1950, retroactively calculated back to 16 May 1949 when the average price of its component stocks was ¥176.21 (equivalent to ¥1,554 in 2024) using a divisor of 225. Since July 2017, the index is updated every 5 seconds during trading sessions.
The Nikkei 225 Futures, introduced at Singapore Exchange (SGX) in 1986, the Osaka Securities Exchange (OSE) in 1988, Chicago Mercantile Exchange (CME) in 1990, is now an internationally recognized futures index.
The Nikkei average has deviated sharply from the textbook model of stock averages, which grow at a steady exponential rate. During the Japanese asset price bubble, the average hit its bubble-era record high on 29 December 1989, when it reached an intraday high of 38,957.44, before closing at 38,915.87, having grown sixfold during the decade.
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This entry incorporates text from “Nikkei 225” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.