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. The Dow has gone through tremendous highs and lows in the last two decades, and hit the 13,000 mark for the first time in 2007.
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