The Standard & Poor's 500 Index (S&P 500) is an index of 500 of the largest U.S. companies, listed on the New York Stock Exchange or NASDAQ, selected by the Standard & Poor's Index Committee based on market capitalization. The S&P 500 Index is a widely recognized barometer of the U.S. equity market. S&P 500 … Continue reading The 4 Best S&P 500 Index Funds