This is a personal capital, which should refer to the index range reflecting the normal, healthy and benign development of the economy. To be honest, I don't know much about stocks. So I searched the following contents for your reference.

2. S & amp； 500 Index is abbreviated as S&; P 500 index is a stock index that records 500 listed companies in the United States. The stock index is created and maintained by Standard & Poor's Company.

All companies covered by the Standard & Poor's 500 Index are listed companies traded on major American exchanges, such as new york Stock Exchange and Nasdaq. Compared with the Dow Jones index, the S&P 500 index contains more companies, so the risk is more dispersed, and it can reflect broader market changes.

Standard & Poor's 500 Index was compiled by Standard & Poor's Company in 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 year to 1942 as the base period, and the index of the base period is set to 10, which 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.