Dow Jones Transportation Average

The Dow Jones Transportation Average (DJTA, also called the "Dow Jones Transports") is a U.S. from S&P Dow Jones Indices of the transportation sector, and is the most widely recognized gauge of the American transportation sector. It is the oldest stock index still in use, even older than its better-known relative, the Dow Jones Industrial Average (DJIA).

The index is a running average of the stock prices of twenty transportation corporations, with each stock's price weighted to adjust for and other factors. As a result, it can change at any time the markets are open. The figure mentioned in news reports is usually the figure derived from the prices at the close of the market for the day.

Changes in the index's composition are rare, and generally occur only after corporate acquisitions or other dramatic shifts in a component's core business. Should such an event require that one component be replaced, the entire index is reviewed. As of April 2010^[update], the index consists of the following 20 companies:Alaska Air Group replaced AMR Corporation on December 2, 2011, after AMR corp. filed for bankruptcy protection. Effective October 30, 2012, Kirby Corp. replaced Overseas Shipholding Group, Inc. On October 15, 2015, American Airlines Group replaced Con-way.

(as of November 12, 2016)

The average was created on July 3, 1884, by Charles Dow, co-founder of Dow Jones & Company, as part of the "Customer's Afternoon Letter". At its inception, it consisted of eleven transportation companies—nine railroads and two non-rail companies:

As a result of the dominating presence of railroads, the Transportation Average was often referred to as "rails" in financial discussions in the early and middle part of the 20th century.

The Transportation Average is an important factor in Dow theory.

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