The Standard & Poor’s 500, often abbreviated as the S&P 500, or just the S&P, is an American stock market index based on the market capitalizations of 500 large companies having common stock listed on the NYSE or NASDAQ. The S&P 500 index components and their weightings are determined by S&P Dow Jones Indices. It differs from other U.S. stock market indices, such as the Dow Jones Industrial Average or the Nasdaq Composite index, because of its diverse constituency and weighting methodology. It is one of the most commonly followed equity indices, and many consider it one of the best representations of the U.S. stock market, and a bellwether for the U.S. economy. The National Bureau of Economic Research has classified common stocks as a leading indicator of business cycles. The S&P 500 was developed and continues to be maintained by S&P Dow Jones Indices, a joint venture majority-owned by S&P Global.
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The S&P 500, or simply the S&P, is a stock market index that measures the stock performance of 500 large companies listed on stock exchanges in the United States. It is one of the most commonly followed equity indices.
The S&P 500 index is a capitalization-weighted index and the 10 largest companies in the index account for 27.5% of the market capitalization of the index. The 10 largest companies in the index, in order of weighting, are Apple Inc., Microsoft, Amazon.com, Facebook, Tesla, Inc., Alphabet Inc. (class A & C), Berkshire Hathaway, Johnson & Johnson, and JPMorgan Chase & Co., respectively. For a list of the components of the index, see List of S&P 500 companies. The components that have increased their dividends in 25 consecutive years are known as the S&P 500 Dividend Aristocrats.:25
Index funds that track the S&P 500 have been recommended as investments by Warren Buffett, Burton Malkiel, and John C. Bogle for investors with long time horizons.
Although the index includes only companies listed in the United States, companies in the index derive on average only 72% of their revenue in the United States.
The index is one of the factors in computation of the Conference Board Leading Economic Index, used to forecast the direction of the economy.
The index is associated with many ticker symbols, including: ^GSPC, INX, and $SPX, depending on market or website. The index value is updated every 15 seconds, or 1,559 times per trading day, with price updates disseminated by Reuters.
The S&P 500 is maintained by S&P Dow Jones Indices, a joint venture majority-owned by S&P Global, and its components are selected by a committee.
Investing in the S&P 500
The easiest way to invest in the S&P 500 is to buy an index fund, either a mutual fund or an exchange-traded fund that replicates, before fees and expenses, the performance of the index by holding the same stocks as the index, in the same proportions. Exchange-traded funds (ETFs) that replicate the performance of the index are issued by The Vanguard Group (NYSE Arca: VOO), iShares (NYSE Arca: IVV), and State Street Corporation (NYSE Arca: SPY). These can be purchased via any electronic trading platform or stockbroker. In addition, mutual funds that track the index are offered by several issuers including Fidelity Investments, T. Rowe Price, and Charles Schwab Corporation.
Direxion offers leveraged ETFs that attempt to produce 3x the daily result of either investing in (NYSE Arca: SPXL) or shorting (NYSE Arca: SPXS) the S&P 500 index.
In the derivatives market, the Chicago Mercantile Exchange (CME) offers futures contracts that track the index and trade on the exchange floor in an open outcry auction, or on CME’s Globex platform, and are the exchange’s most popular product. Ticker symbols are /SP for the full-sized contract and /ES for the E-mini S&P contract that is one fifth the size of /SP. In May 2019, the CME started trading a Micro E-mini futures contract that is one tenth the size of the S&P E-mini contract, i.e. 1/50 the size of the full-sized (SP) contract. The Micro E-mini S&P 500 Index contract’s ticker symbol is /MES.
The Chicago Board Options Exchange (CBOE) offers options on the S&P 500 index as well as on S&P 500 index ETFs, inverse ETFs, and leveraged ETFs.
In 1860, Henry Varnum Poor formed Poor’s Publishing, which published an investor’s guide to the railroad industry.
In 1923, Standard Statistics Company (founded in 1906 as the Standard Statistics Bureau) began rating mortgage bonds and developed its first stock market index consisting of the stocks of 233 U.S. companies, computed weekly.
In 1926, it developed a 90-stock index, computed daily.
In 1941, Poor’s Publishing merged with Standard Statistics Company to form Standard & Poor’s.
On March 4, 1957, the index was expanded to its current 500 companies and was renamed the S&P 500 Stock Composite Index.
In 1962, Ultronic Systems became the compiler of the S&P indices including the S&P 500 Stock Composite Index, the 425 Stock Industrial Index, the 50 Stock Utility Index, and the 25 Stock Rail Index.
On August 31, 1976, The Vanguard Group offered the first mutual fund to retail investors that tracked the index.
On April 21, 1982, the Chicago Mercantile Exchange began trading futures based on the index.
On July 1, 1983, Chicago Board Options Exchange began trading options based on the index.
On January 22, 1993, the Standard & Poor’s Depositary Receipts exchange-traded fund issued by State Street Corporation began trading.
On September 9, 1997, CME Group introduced the S&P E-mini futures contract.
In 2005, the index transitioned to a public float-adjusted capitalization-weighting.
Like other indices managed by S&P Dow Jones Indices, but unlike indices such as the Russell 1000 which are strictly rule-based, the components of the S&P 500 index are selected by a committee. When considering the eligibility of a new addition, the committee assesses the company’s merit using eight primary criteria: market capitalization, liquidity, domicile, public float, Global Industry Classification Standard and representation of the industries in the economy of the United States, financial viability, length of time publicly traded, and stock exchange. Over the past few years, there has been a decline in the number of S&P 500 companies with classified boards.:159 Requirements to be added to the index include:
To remain indicative of the largest public companies in the United States, the index is reconstituted quarterly; however, efforts are made to minimize turnover in the index as a result of declines in value of constituent companies.
A stock may rise in value when it is added to the index since index funds must purchase that stock to continue tracking the index.
Index value calculation
The index is a free-float capitalization-weighted index;:150 that is, companies are weighted in the index in proportion to their market capitalizations. For purposes of determining the market capitalization of a company for weighting in the index, only the number of shares available for public trading (“public float”) is used; shares held by insiders or controlling shareholders that are not publicly traded are excluded from the calculation.
The formula to calculate the S&P 500 index value is:
where is the price of the i-th stock in the index, is the corresponding number of shares publicly available (“float”) for that stock, and is a normalization factor.
The , currently below 8.3 billion, is a number that is adjusted to keep the value of the index consistent despite corporate actions that affect market capitalization and would otherwise affect the calculation formula, such as additional share issuance, share buybacks, special dividends, constituent changes, rights offerings, and corporate spin-offs. Stock splits do not affect the divisor since they do not affect market capitalization. When a company is dropped and replaced by another with a different market capitalization, the divisor needs to be adjusted in such a way that the value of the S&P 500 index remains constant. All divisor adjustments are made after the close of trading and after the calculation of the closing value of the S&P 500 index.:290
The average annual total return and compound annual growth rate of the index, including dividends, since inception in 1926 has been approximately 9.8%, or 6% after inflation; however, there were several years where the index declined over 30%. The index has posted annual increases 70% of the time. However, the index has only made new highs on 5% of trading days, meaning that on 95% of trading days, the index has closed below its all-time high.
On August 12, 1982, the index closed at 102.42.
On Black Monday (1987), the index realized its worst daily percentage loss, falling 20.47% in a single day.
In October 1996, the index closed above 700.
On February 12, 1997, the index closed above 800 for the first time.
On February 2, 1998, the index closed above 1,000 for the first time.
On March 24, 2000, at the peak of the dot-com bubble, the index reached an intraday high of 1,552.87; this high was not exceeded until May 30, 2007. On October 10, 2002, during the stock market downturn of 2002, the index fell to 768.83, a decline of approximately 50% from its high in March 2000.
On May 30, 2007, the index closed at 1,530.23, setting its first all-time closing high in more than 7 years. The index achieved a new all-time intraday high on October 11, 2007 at 1,576.09.
Between the bankruptcy of Lehman Brothers on September 15, 2008, and the end of 2008, the index closed either up or down 3% in one day 29 times. On October 13, 2008, the index closed up 11.6%, its best single-day percentage gain since being founded in 1957.
On November 20, 2008, the index closed at 752.44, its lowest since early 1997.
The index ended 2008 at 903.25, a yearly loss of 38.5%. The index continued to decline in early 2009, closing at 676.53 on March 9, 2009, its lowest close in 13 years. The drawdown from the high in October 2007 to the low in March 2009 was 56.8%, the largest since World War II.
At the trough of the United States bear market of 2007–2009, on March 6, 2009, the index was at 666. By March 23, 2009, the index had risen 20% from its low, closing at 822.92.
The index closed 2009 at 1,115.10, the second-best year of the decade.
On April 14, 2010, the index closed at 1,210.65, its first close above 1,200 since the financial crisis of 2007-2008. By July 2, 2010, it had fallen to 1,022.58, its lowest point of the year.
On April 29, 2011, the index closed at a post-crisis high of 1,363.61. However, after the August 2011 stock markets fall, on October 4, 2011, the index briefly broke below 1,100.
The index rose 13% in 2012 despite significant volatility amid electoral and fiscal uncertainty and round 3 of quantitative easing. On December 31, 2012, the index closed at 1,426.19, an annual gain of 13% and its biggest gain in 3 years.
On March 28, 2013, the index surpassed its closing high of 1,565.15, recovering all its losses from the Great Recession. On April 10, 2013, it closed above the intraday high from 2007.
On August 26, 2014, the index closed above 2,000 for the first time.
On March 2, 2015, the index reached an all-time closing high, while the Nasdaq Composite closed above 5,000 for the first time since 2000.
After the 2015–2016 Chinese stock market turbulence, a period of over a year with no new record highs ended on July 11, 2016, with the index closing at 2,137.16.
In June 2017, the index posted the largest weekly rise since the 2016 United States presidential election.
For the full year 2017, the index was up 19.4%, its best year since 2013. On September 25, 2017, the index closed above 2,500 for the first time.
The index rose sharply in January 2018, extending one of its longest monthly winning streaks, only to fall 4% in February 2018 during a month of extremely high volatility, including a day in which the VIX doubled. It was the first monthly decline in 11 months. In the third quarter of 2018, the index posted its best quarter since 2013. However, the index fell 11% in the month of December 2018, its worst December performance since the Great Depression. The index fell 6% in 2018, its worst year in a decade.
However, in 2019, the index posted its best first half in 22 years including the best June since 1938. On July 10, 2019, the index reached 3,000 for the first time. The index rose 31.5% in 2019, one of its best years.
On February 19, 2020, the index hit a new closing peak of 3,386.15, only to fall 10% in the next 6 trading days, its fastest drop from a new peak. By the 2020 stock market crash low on March 23, 2020, the index had fallen 34% from its peak. The index fell 20% during the first quarter of 2020, its worst quarter since 2008. This was followed by a 20% gain in the second quarter, its biggest quarterly gain since 1998. It had quickly recovered from its COVID-19 crash over a 6 month span and hit a new record on August 18, 2020.
Returns are generally quoted as price returns (excluding returns from dividends). However, they can also be quoted as total return, which include returns from dividends and the reinvestment thereof, and “net total return”, which reflects the effects of dividend reinvestment after the deduction of withholding tax.
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