Dow Jones Industrial Average Index

Created by the Wall Street Journal editor and the co-founder of Dow Jones & Company, Charles Dow, the Dow Jones Industrial Average is an average of the 30 largest and most widely held public companies in the United States. Next to the Dow Jones Transportation Average, the DIJA is the oldest continuing U.S. market index.

Although 'industrial' is in the title, the companies represented in the DIJA have not much in common with heavy industry. Instead of an actual average, a scaled average of these blue-chip stocks is used in order to compensate for the effect of stock splits and other adjustments. To calculate the value of the DIJA, the sum of the component prices is divided by a divisor, which is changed over time. The DIJA is also quoted in points rather than dollars.