The Wilshire 5000?

You are aware that there are many stock market indices. The Wilshire 5000, which was started in 1974, is designed to include the return of every stock in the market and is so named because there were originally about 5,000 stocks in the index. However, over the years, stocks have been added and subtracted from the index. So, would it surprise you that the index currently tracks only about 3,600 stocks? The reason is that the number of U.S. stocks has shrunk in recent years, from a high of about 8,800 in 1997 to around 4,900 at the end of 2012. Numerous causes have likely contributed to the reduction, including failed companies, an increase in mergers and acquisitions, and a decrease in the number of IPOs.