Guotai Junan Securities is the largest securities company in China, and it is a Class A AAA securities company, which is famous for its steady operation. Hedging is one of the important functions of stock index futures. Hedging means that investors buy or sell futures contracts with the same spot amount but in the opposite direction, so as to make up for the actual losses caused by price fluctuations in the spot market by selling or buying futures contracts at some future time. In this way, the trading gains and losses of futures and spot markets are "set" together.