Doug is a Chartered Alternative Investment Analyst who spent more than 20 years as a derivatives market maker and asset manager before “reincarnating” as a financial media professional a decade ago.
Before joining Britannica, Doug spent nearly six years managing content marketing projects for a dozen clients, including The Ticker Tape, TD Ameritrade’s market news and financial education site for retail investors. He has been a CAIA charter holder since 2006, and also held a Series 3 license during his years as a derivatives specialist.
Doug previously served as Regional Director for the Chicago region of PRMIA, the Professional Risk Managers’ International Association, and he also served as editor of Intelligent Risk, PRMIA’s quarterly member newsletter. He holds a BS from the University of Illinois at Urbana-Champaign and an MBA from Illinois Institute of Technology, Stuart School of Business.
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Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.
The S&P 500 is a broad-based stock market index that tracks roughly 500 publicly traded companies based in the United States. It is considered by many investors and analysts to be the best overall measurement of American stock market performance.
S&P Global (formerly Standard & Poorâs), which sponsors a number of other market indexesâand also operates one of the âBig Threeâ credit rating agenciesâtraces its roots to an investment information service begun in 1860 by Henry Varnum Poor. In 1941, Poorâs original company, Poorâs Publishing, merged with Standard Statistics (founded in 1906 as the Standard Statistics Bureau) and assumed the name Standard and Poorâs Corporation, a provider of financial information and analysis.
The S&P 500 (SPX), formerly called the Composite Index (and later Standard & Poorâs Composite Index), had been launched on a small scale in 1923. It began tracking 90 stocks in 1926 and expanded to 500 in 1957. Unlike the Dow Jones average, the S&P 500 is weighted by market capitalization, meaning that it computes a weighted average of the stocks constituting the index. As a result, the stocks with a larger market valuation have a greater impact on the overall index.
Confused about market cap?
A companyâs market capitalization (âmarket capâ) represents a companyâs total value. Itâs calculated by multiplying the companyâs share price by the number of shares outstanding. Learn more about market cap, index weighting, and your investing strategy.
The companies listed on the S&P 500 represent a whoâs who of U.S. industry, and additions and deletions from the list often indicate market trends. Some of the top-weighted companies in the index include Apple, Inc., Microsoft Corp., Amazon.com, and Tesla, Inc.
The S&P 500 consists of 11 sectors: energy, information technology, consumer staples, consumer discretionary, utilities, real estate, communication services, financial services, industrial, materials, and health care.
