The Wilshire 5000 Total Market Index represents the broadest index for the U.S. equity market, measuring the performance of all U.S. equity securities with readily available price data. No other index comes close to offering its comprehensiveness. When the index was created in 1974 Wilshire's founder took advantage of then-new technologies that made it possible to collect stock prices and calculate returns for a volume of issues never before brought together. The index was named after the nearly 5,000 stocks it contained when it was originally created, but it has grown to include over 5,000 issues, reflecting the growth in U.S. equity issues as a whole.

In 1983 the Wilshire 4500 Index was created by removing the 500 stocks in the S&P 500 from the Wilshire 5000. Medium and small capitalization managers use the Wilshire 4500 as a performance benchmark.

Barron's was the first to publish the Wilshire 5000 Index on January 13, 1975. Now the Wilshire 5000 is published daily in a variety of outlets, including print, television, and online media. As the broadest measure of the U.S. equity market, it is watched by all major institutions, including the Federal Reserve Board.

Click here for background on various Wilshire index families.