Historical data for the Dow Jones in 1986 can be found on Yahoo Finance. The Dow Jones Industrial Average for 1986 was 17,776.12, with a decrease 200.19 or 1.11 percent.
Invented by Charles Dow in 1896, the Dow Jones Industrial Average (DJIA) is an average of 30 notable stocks traded on the NASDAQ and New York Stock Exchange. The Dow Jones is price-weighted, and it is often used as a measure of the stock market in general. Current stocks tracked by the Dow Jones include Walmart Stores, Disney, Exxon Mobile and General Electric, to name a few. These stocks represent some of the largest and most significant companies traded on American stock exchanges, which is why they are used as a measure of the economy.
It's important to recognize that while the Dow Jones does mark the changes among some of the most influential stock traded in America, it is not necessarily a perfect sample for the stock market as a whole. In some cases, times when the Dow Jones experienced the greatest increases were times when the majority of companies were experiencing very little increase (or even loss) in stock value. As a whole, the Dow Jones remains a widely used and trusted indicator for the state of the stock market.