S&P curve is the Standard & Poor's 500 Index, which was compiled by S&P Company at 1957. The initial constituent stocks include 425 industrial stocks, 15 railway stocks and 60 public utility stocks. From 1 June 65438+July1,its constituent stocks were changed to 400 industrial stocks, 20 transportation stocks, 40 public utilities stocks and 40 financial stocks. It takes 194 1 to 1943 as the base period, and the base period index is set to 10. It is calculated by the weighted average method, with the listed amount of the stock as the weight, and the weighted calculation is carried out according to the base period. Compared with the Dow Jones Industrial Average, the Standard & Poor's 500 Index has the characteristics of wide sampling area, strong representativeness, high accuracy and good continuity, and is generally regarded as the ideal target of stock index futures contracts.