As of October 2015, the highest closing of the Dow Jones Industrial Average is 18,312.39, which occurred on May 19th, 2015. The Dow Jones measures the activity of the stock market by tracking the share prices of 30 companies that best represent their industries.
Dow Jones also compiles two other averages, the Dow Jones Utility Average and the Dow Jones Transportation Average. These three Dow averages help determine the U.S. economy's future movements and are the most-quoted indicators among stock market analysts in the U.S. The Dow Jones market average was conceptualized by Wall Street Journal editor Charles Dow in 1885, and the first Dow Jones Industrial Average was published in 1896.