An index that measures stock prices on the Tokyo Stock Exchange (TSE). This capitalization-weighted index lists all firms that are considered to be under the 'first section' on the TSE, which groups all of the large firms on the exchange into one pool. The second section groups all of the remaining smaller firms. |||The TOPIX is believed to be more representative of the Japanese stock markets than the Nikkei because of the more fair representation of price changes and the inclusion of all the largest companies on the exchange.Currently, about 1,600 first section companies are listed on the TSE, along with 500 second section companies.