The DOW Jones industrial average was founded on May 26, 1896 and represented the average of 12 stocks from important American industries. Only GE is currently part of the index. The other eleven were:

American Cotton Oil Company, distant ancestor of Bestfoods, now part of Unilever
American Sugar Company, now Domino Foods, Inc.
American Tobacco Company, broken up in 1911 antitrust action
Chicago Gas Company, bought by Peoples Gas Light in 1897 (now an operating subsidiary of Integrys Energy Group, Inc.)
Distilling & Cattle Feeding Company, now Millennium Chemicals, a division of LyondellBasell
Laclede Gas Light Company, still in operation as The Laclede Group, removed from the Dow Jones Industrial Average in 1899
National Lead Company, now NL Industries, removed from the Dow Jones Industrial Average in 1916
North American Company, (Edison) electric company broken up in the 1940s
Tennessee Coal, Iron and Railroad Company in Birmingham, Alabama, bought by U.S. Steel in 1907
U.S. Leather Company, dissolved 1952
United States Rubber Company, changed its name to Uniroyal in 1961, merged private with B.F. Goodrich in 1986, bought by Michelin in 1990.

In 1916, the number of stocks in the index was increased to twenty.

Finally, it was increased to thirty stocks in 1928, near the height of the "roaring 1920s" bull market. The crash of 1929 and the ensuing Great Depression returned the average to its starting point, almost 90% below its peak.

With the current inclusion of only 30 stocks, critics like Ric Edelman argue that the DJIA is not a very accurate representation of the overall market performance even though it is the most cited and most widely recognized of the stock market indices.[12]

Additionally, the DJIA is criticized for being a price-weighted average, which gives relatively higher-priced stocks more influence over the average than their lower-priced counterparts, but takes no account of the relative size or market capitalization of the components. For example, a $1 increase in a lower-priced stock can be negated by a $1 decrease in a much higher-priced stock, even though the first stock experienced a larger percentage change. In addition, a $1 move in the smallest component of the DJIA has the same effect as a $1 move in the largest component of the index. As of March 2009, IBM is the highest priced stock in the index and therefore has the greatest influence on it. Many critics of the DJIA recommend the float-adjusted market-value weighted S&P 500 or the Dow Jones Wilshire 5000, the latter of which includes all U.S. securities with readily available prices, as better indicators of the U.S. market.