Nikkei225 (日経平均株価, Nikkei heikin kabuka, 日経225) is a stock market index for the Tokyo Stock Exchange (TSE). The Nikkei average is the most watched index of Asian stocks. It has been calculated daily by the Nihon Keizai Shimbun (Nikkei) newspaper since 1971. It is a price-weighted average (the unit is Yen), and the components are reviewed once a year.