S&P 500 Index

Formally known as the S&P 500 Composite Stock Price Index, the S&P 500 was introduced in 1957 and was initially a market capitalization weighted index but switched to being a float weighted index in 2005. The index consists of 500 stocks traded on the New York Stock Exchange (NYSE), American Stock Exchange (AMEX) and the Nasdaq National Market System (NASDAQ) and is the industry standard for portfolio performance benchmarking. Mutual funds which are unable to beat the S&P 500 are considered to be underperforming.

The S&P 500 comprises leading companies that are representative of various industries in the United States economy. No coincidence that many of the component stocks are large cap companies with average market capitalization of about $26 billion. Total market capitalization of all the companies in the S&P 500 exceeds $11 trillion.


The selection process is performed by an autonomous S&P Index Committee. No company can apply or be nominated for inclusion into the index.

Addition Criteria

  1. Only U.S. companies can be included.
  2. Adequate liquidity with reasonable stock price.
  3. Market capitalization of $5 billion and above.
  4. Financial viability, typically measured as four consecutive quarters of positive reported GAAP earnings.
  5. Public float of at least 50%.
  6. IPOs can only be considered 6 to 12 months after their launch.
  7. Company must not be a closed-end fund, holding company, partnership, investment vehicle or royalty trust. REITs and BDCs are eligible for inclusion.
  8. Sector balance for the index must be maintained after inclusion of the company.

Companies that meet the above criteria are placed in a replacement pool, ready to be included into the index when there is a vacancy.


Standard & Poor believes that turnover in index membership should be avoided whenever possible. Hence companies which were added to the index usually stays in the index unless too many of the addition criteria has been violated or if the company no longer exist due to mergers and acquisitions.

S&P MidCap 400 & S&P SmallCap 600

Smaller companies have high reward/high risk profiles while larger companies typically have a low reward/low risk profiles. Hence the size of a company is a determinant of asset class but because S&P 500 companies are predominantly large and mid caps, the S&P MidCap 400 and S&P SmallCap 600 indices were introduced. S&P MidCap 400 comprises companies with market capitalization of between $1.5 billion and $5.5 billion while S&P SmallCap 600 comprises companies with market value of between $300 million and $2 billion. Together, they combine to form the S&P 1000 index.

Related Links

Ready to Start Trading?

Open an account at OptionsHouse.com and get 100 commission-free trades + free virtual trading tool!

Your new trading account is immediately funded with $5,000 of virtual money which you can use to test out your trading strategies using OptionHouse's virtual trading platform without risking hard-earned money.

Once you start trading for real, your first 100 trades will be commission-free! (Make sure you click thru the link below and quote the promo code '60FREE' during sign-up)

Click here to open a trading account at OptionsHouse.com now!

Join the Discussions @ The Options Forum

Beginners Questions

Advanced Strategy Talks

RSS Feed Widget

Trading Ideas & Opportunities

Home | About Us | Terms of Use | Disclaimer | Privacy Policy | Sitemap

Copyright 2016. TheOptionsGuide.com - All Rights Reserved.