The SSE Composite Index, often referred to as the Shanghai index, is a stock market index that tracks the performance of all stocks traded on the Shanghai Stock Exchange. First introduced in 1991, it has soon become one of the most widely used indices of the Chinese stock market. It's a capitalization-weighted index representing the 20-year-history of the China Capital Markets' development. SSE Index has subindices such as SSE 50 Index and SSE 180 Index tracking the corresponding number of top companies of the Shanghai Stock Exchange.