The S&P 500 is a far more accurate index of market trends than the Dow. The people in charge of the Dow also like to change the companies listed to achieve more "optimistic" results:

"On November 1, 1999, Chevron, Goodyear Tire and Rubber Company, Sears Roebuck, and Union Carbide were removed from the DJIA and replaced by Intel, Microsoft, Home Depot, and SBC Communications. Intel and Microsoft became the first two companies traded on the NASDAQ exchange to be listed in the DJIA. On April 8, 2004, another change occurred as International Paper, AT&T, and Eastman Kodak were replaced with Pfizer, Verizon, and AIG. On December 1, 2005, AT&T returned to the DJIA as a result of the SBC Communications and AT&T merger. Altria Group and Honeywell were replaced by Chevron and Bank of America on February 19, 2008."