The Wilshire 5000 Total Market Index, or more simply the Wilshire 5000, is a market-capitalization-weighted index of the market value of all American-stocks actively traded in the United States. As of March 31, 2022, the index contained 3,660 components. The index is intended to measure the performance of most publicly traded companies headquartered in the United States, with readily available price data, (Bulletin Board/penny stocks and stocks of extremely small companies are excluded). Hence, the index includes a majority of the common stocks and REITs traded primarily through New York Stock Exchange, NASDAQ, or the American Stock Exchange. Limited partnerships and ADRs are not included. It can be tracked by following the ticker ^W5000. History The Wilshire 5000 Total Market Index was established by the Wilshire Associates in 1974, naming it for the approximate number of issues it included at the time. It was renamed the "Dow Jones Wilshire 5000" in April 2004, after Dow Jones & Company assumed responsibility for its calculation and maintenance. On March 31, 2009, the partnership with Dow Jones was terminated and the index returned to Wilshire Associates. The base value for the index was 1404.60 points on base date December 31, 1980, when it had a total market capitalization of US$1,404.596 billion. On that date, each one-index-point change in the index was equal to $1 billion. However, index divisor adjustments due to corporate actions and index composition changes have changed the relationship over time, so that by 2005 each index point reflected a change of about $1.2 billion in the index's total market capitalization. The index increased tenfold in less than twenty years from its base date, peaking at a 20th-century closing record high of 14,751.64 points on March 24, 2000, a level that would not be surpassed until February 20, 2007. A hypothetical investment in the Wilshire 5000, made at the 2000 peak and with subsequent dividends reinvested, did not become profitable on a closing basis until October 3, 2006. On April 20, 2007, the index closed above 15,000 for the first time. On that day, the S&P 500 was still several percentage points below its March 2000 high, because small cap issues absent from the S&P 500 and included in the Wilshire 5000 outperformed the large cap issues that dominate the S&P 500 during the cyclical bull market. The index reached an all-time high on October 9, 2007, at the 15,806.69 point