Standard & Poor's 500 Composite Stock Price Index - The S&P 500 measures the total investment return of 500 common stocks, which are chosen by Standard & Poor's Corporation on a statistical basis. The 500 securities, most of which trade on the NYSE, represent about 70 percent of the market value of all U.S. common stocks. Typically, companies included in the S&P 500 are the largest and most dominant firms in their industries.

Wilshire 5000 Index - This market capitalization-weighted index consists of all publicly traded U.S. stocks, and provides an overall view of the U.S. stock market. More than 6,000 equities are included in the index. It's used to measure the performance of stocks as a whole, as opposed to a particular segment of the stock market.