The Dow Jones industrial average is a stock index measuring the value of 30 blue chip companies, which represent industries driving the U.S. stock market. Created in 1896 by Charles Dow, the index usually accounts for 25 to 30 percent of the market value of U.S. stocks. Earlier this year, Dow Jones & Co. announced that Travelers Cos. and Cisco Systems would replace Citigroup and General Motors in the index.
Copyright 2009 NPR