S&P 500

American stock market index

The Standard and Poor's 500,[1] or sometimes known as the S&P 500,[2] is something that measures the stock market, looking at how well 500 of the largest companies listed on stock exchanges in the United States are doing. It is one of the most commonly used ways of looking at stocks for these companies. There is over $4.6 trillion invested in the companies that use how well companies are doing to know when to invest.[1]

A linear chart of the S&P 500 day by day closing values from January 3, 1950 to February 19, 2016
A logarithmic chart of the S&P 500 index daily closing values from January 3, 1950 to February 19, 2016.

Included companies


The 10 largest companies in the index are responsible for 26.4% of the tied investments. The 10 largest companies in the S&P 500, in order of size, are Apple Inc., Microsoft, Amazon.com, Facebook, Alphabet Inc. (class A & C), Tesla, Inc., Berkshire Hathaway, JPMorgan Chase, and Johnson & Johnson.[1] For a list of companies in the S&P 500, see List of S&P 500 companies.[3]: 25 

Index funds that look at how well the S&P 500 are doing have been suggested as things to invest in by Warren Buffett, Burton Malkiel, and John C. Bogle for investors with long time horizons.[4]

Although the S&P 500 includes only companies that are available to be sold in stocks in the United States, companies in the S&P 500 on average only get 72% of their money from the United States.[5]

The S&P 500 is one of the ways used to calculate the Conference Board Leading Economic Index, used to predict if the economy will do better or worse in the future.[6]

It is associated with many ticker symbols, including: ^GSPC,[7] INX,[8] and $SPX, but this changes by market or website.[9] The index value is updated every 15 seconds, or 1,559 times per trading day, with price updates updated with help from Reuters.[10]



The S&P 500 is kept up-to-date by S&P Dow Jones Indices, a joint venture mostly owned by S&P Global[11][12]


  1. 1.0 1.1 1.2 "S&P 500®". S&P Global.
  2. Reklaitis, Victor (October 30, 2015). "The S&P is up 9% this month, but these 10 stocks jumped more than 22%". MarketWatch. Archived from the original on November 16, 2018.
  3. Lichtenfeld, M. (2012). Get Rich with Dividends: A Proven System for Earning Double-Digit Returns. Hoboken, New Jersey: Wiley. p. 25. ISBN 9781118282342.
  4. Martin, Emmie (June 28, 2018). "Warren Buffett and Tony Robbins agree on the best way to invest your money". CNBC.
  5. Brzenk, Phillip (March 19, 2018). "The Impact of the Global Economy on the S&P 500®" (PDF). S&P Global.
  6. "Global Business Cycle Indicators". The Conference Board.
  7. "Yahoo! Finance: ^GSPC". Yahoo! Finance.
  8. "Google Finance: .INX". Google Finance.
  9. "S&P 500 Index Quote". MarketWatch.
  10. Duggan, Wayne (June 13, 2019). "This Day In Market History: S&P 500 Quotes Delivered Every 15 Seconds". Benzinga.
  11. Preston, Hamish (June 9, 2020). "Higher Turnover Ahead For S&P 500? Not Necessarily!". S&P Global.
  12. Wathen, Jordan (April 9, 2019). "How Are S&P 500 Stocks Chosen?". The Motley Fool.