WHAT AVERAGE REPRESENTS

The Dow Jones industrial average was invented 100 years ago by Charles Henry Dow, a publisher of the Customers Afternoon Letter, a stock market newsletter that was a forerunner to the now-famous Wall Street Journal.

The first Dow had only 11 stocks -- nine of them railroads, reflecting the importance of the iron horse in the 19th century.

The stocks on the Dow Average increased over the years, reaching 30 on Oct. 1, 1928. The Dow Jones Average still consists of 30 stocks, although many of the companies have changed.

The industrials average, the one most used by investors, computes the average price of the common stocks prices of the 30 selected companies traded on the New York Stock Exchange.

The Average is still maintained by Dow Jones & Co., which publishes the Wall Street Journal and Barron's.

The Dow industrials have changed through the years, with the most recent shift in 1991 when Walt Disney, J.P. Morgan and Caterpillar became Dow 30 stocks, replacing three other companies.