The Wilshire 5000 is a U.S. stock-market index designed to represent nearly the entire investable equity market.
Wilshire Associates created the index in 1974. Its name originally reflected approximately 5,000 constituent companies, although the number of stocks has changed over time and is not fixed. The index covers eligible publicly traded U.S. companies across large-, mid-, small-, and micro-capitalization segments.
The Wilshire 5000 is weighted by market capitalization, meaning larger companies have greater effects on its value. It is therefore broader than indexes focused on blue-chip companies, large technology companies, or small-cap shares.
The index is sometimes described as a total-market benchmark, but it does not literally include every U.S.-related security. Eligibility rules exclude certain securities and listings, and the investable universe changes as companies enter, leave, merge, or become delisted.