S&P 500 Index ($SPX)
Standard & Poor’s 500
An index of 500 stocks chosen for market size, liquidity and industry grouping, among other factors. The S&P 500 is designed to be a leading indicator of U.S. equities and is meant to reflect the risk/return characteristics of the large cap universe.
Companies included in the index are selected by the S&P Index Committee, a team of analysts and economists at Standard & Poor’s. The S&P 500 is a market value weighted index – each stock’s weight is proportionate to its market value.
Other popular Standard & Poor’s indexes include the S&P 600, an index of small cap companies with market capitalizations between $300 million and $2 billion, and the S&P 400, an index of mid cap companies with market capitalizations of $2 billion to $10 billion.
Because it contains 500 companies, the S&P 500 represents overall market performance better than the Dow Jones Industrial Average’s (DJIA) 30 companies. Money managers and financial advisors actually watch the S&P 500 stock index more closely than the DJIA.
A number of financial products based on the S&P 500 are available to traders. These include index funds and exchange-traded funds. However, it would be difficult for individual traders to buy the index, as this would entail buying 500 different stocks.
S&P doesn’t set the 500 companies they track in stone. S&P can add or remove companies when market conditions change. They can remove a company if it isn’t doing well or goes bankrupt, and they can replace a company in the index with another company that is doing better.