The weighting of each company in the index is calculated by taking the company's market cap and dividing it by the total market cap of the index.2 Other S&P Indices The S&P 500 is a part of the S&P Global 1200 family of indices. Other indices include theS&P MidCap 400which repre...
TheS&P 500is another Standard & Poor's index that was launched in 1997.6It is a market-capitalization-weighted index comprised of 500 of the largest companies in the United States. As such, it is considered the best gauge of the U.S. large-cap market.7Like the S&P MidCap 400 Index, i...
It is not an exact list of the top 500 U.S. companies bymarket capbecause there are other criteria that the index includes. Still, the S&P 500 index is regarded as one of the best gauges of prominent American equities' performance, and by extension, that of the stock market overall. Ke...