The Dow Jones Industrial Average (DJIA) is a price-weighted stock market index created in 1896 by Charles Dow that consists of 30 large-cap, blue-chip companies. Today's Dow Jones Industrial Average components are ironically non-industrial; only about 16% of its companies are classified as industrials - the same representation as the information technology sector. The components, which are maintained and reviewed by editors of the Wall Street Journal, have changed 48 times since over the years. Here is a look at some of the DJIA's top position holders, as well as two companies that have recently lost their prestigious standings.

TUTORIAL: Stock Basics

Alcoa (NYSE:AA)
Alcoa, the world's leading producer of primary and fabricated aluminum, has been a DJIA component since 1959. Conducting operations in 31 countries, Alcoa is involved in all aspects of the aluminum industry including technology, mining, refining, fabricating, smelting and recycling. Originally listed as the Aluminum Company of America, it became Alcoa in 1999. In 1925, Alcoa listed its stock on the New York Curb Exchange, the forerunner of the American Stock Exchange. The company listed on the NYSE in 1951 and eight years later was included in the DJIA. Alcoa is also an S&P 500 component. (For related reading, see An Introduction To The Dow Jones Industrial Average.)

DuPont (NYSE:DD)
E. I. du Pont de Nemours and Company, most often referred to as DuPont, was formed in 1802 as a gunpowder mill by Eleuthère Irénée du Pont. DuPont grew rapidly and become the leading supplier of gunpowder to the U.S. military, providing half of the gunpowder that was needed by the Union Army during the American Civil War. Today, DuPont is a science-based products and services company behind brands like Corian, Teflon, Mylar, Kevlar and Lycra. DuPont joined the DJIA for a brief stint in 1924-1925, then again on November 20, 1935 where it has remained ever since. It is also an S&P 500 component.

ExxonMobil (NYSE:XOM)
ExxonMobil is an American multinational oil and gas corporation formed by the 1999 merger between Exxon and Mobil. Both of these companies were descendants of Standard Oil. Following a Supreme Court decision that ruled Standard Oil must be dissolved and split into 34 companies, Jersey Standard and Socony emerged, eventually becoming Exxon and Mobil, respectively. ExxonMobil is one of the world's largest publicly-traded companies and is the largest of the six oil supermajors as measured by market capitalization, cash flow, revenues and profits. ExxonMobil is also an S&P 500 component. (For background reading, see Why The Dow Matters.)

General Electric (NYSE:GE)
General Electric Company was formed in 1892 as a result of a merger between Edison General Electric Company (established in 1878 as Edison Electric Light Company by Thomas Edison) and Thomson-Houston Electric Company. General Electric was ranked by Fortune in 2011 as the sixth-largest firm in the United States and the 14th most profitable. A multinational conglomerate corporation, GE is the only company listed in today's DJIA that was also a part of the original index in 1896. Following a brief respite in the early 1900s when it was not listed on the DJIA, GE has held a steady and prominent spot since November 7, 1907.

Proctor & Gamble (NYSE:PG)
Proctor & Gamble is a Fortune 500 American multinational corporation that was founded in 1837 by William Proctor, a candlemaker, and James Gamble, a soapmaker. This prominent company has been around so long that it won military contracts to supply the Union Army with soap and candles during the American Civil War. Headquartered in Cincinnati, Ohio, P&G manufactures a variety of consumer goods including Pampers, Crest and Gillette. Proctor & Gamble has held a steady spot on the Dow Jones Industrial Average since May 26, 1932.

Two companies held esteemed spots on the Dow Jones Industrial Average only to lose them during the recent financial crisis:

Citigroup (NYSE:C)
The financial giant joined the DJIA in 1997 and was eventually removed from the Dow in 2009 following declining performance, a negative long-term outlook and the government's large stake in the company. Citigroup initially joined the DJIA as Citicorp, later merging with Travelers to form Citigroup in 1998. In 2002, Citigroup spun off The Travelers Companies, Inc (NYSE:TRV), a large home, auto and commercial insurer. Ironically, Citigroup was replaced by Travelers in the DJIA.

General Motors (NYSE:GM)
General Motors had been a DJIA component for more than 80 years before being kicked off in 2009 after filing for Chapter 11 bankruptcy protection. Shares had fallen to 75 cents, down from its peak above $93 per share in 2000. GM was added to the index twice - first in 1915 for 18 months, and again in 1925 for a run that totalled 83 years. General Electric is the only current company that has held a position on the Dow for longer than GM. Cisco Systems, which is based in San Jose, California, replaced General Motors on the index on June 8, 2009. (For more, see What's The Difference Between The DJIA and The S&P 500?)

The Bottom Line
The Dow Jones Industrial Average, currently owned by the CME Group, is one of the world's most closely watched stock market indexes, and is used by millions of investors to gauge progress in the stock market. When news reporters indicate "the market was up today" they are often referring to the performance of the DJIA. Companies that hold one of the 30 spots on the DJIA typically have established records of stable earnings power, long records of dividend payments, strong balance sheets and high credit ratings. These characteristics, along with their industrial leadership, help companies earn - and keep - a coveted spot on the Dow.

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