S&P 500

Established in 1957, the S&P 500, also known as the Standard and Poor’s 500 Index, is a capitalization-weighted index of 500 large-cap common stocks. Capitalization-weighted means that the companies with largest stock market capitalization have the greatest impact on the value of the index. The S&P 500 is the second most widely followed stock market index in America after the Dow Jones Industrial Average.