The SSE Composite Index is a stock market index that tracks all the stocks listed on the Shanghai Stock Exchange in China. It serves as a key indicator of the performance of the Chinese stock market and includes both A-shares and B-shares. Investors use this index to gauge market trends and make informed investment decisions. Launched in 1991, the SSE Composite Index is calculated using a market capitalization-weighted methodology. This means that companies with larger market values have a greater impact on the index's movements. It is widely followed by investors, analysts, and policymakers to assess the overall health of the Chinese economy.