Genesee & Wyoming and More Big Movers in Transportation on December 21, 2012

The Nasdaq has declined 2%, the S&P 500 has decreased 1.9% and the Dow has fallen 1.4%, marking a bad morning for the market. The transportation sector is a category of stocks relating to the transportation of goods or customers. It is made up of airlines, railroads and trucking companies. The performance of the transportation sector is sensitive to the price of oil. Because operations revolve around the use of vehicles, fuel prices represent a significant cost to transportation companies. As the price of oil rises, transportation companies will be expected to earn less. Inversely, these companies do well when the cost of fuel decreases.

The Transportation sector (IYT) is currently ahead of the overall market, down only 0.9%, and its biggest movers are currently:

Company	Market Cap	Percentage Change
American Railcar Industries (Nasdaq:ARII)	$707 million	-4.9%
GulfMark Offshore (NYSE:GLF)	$948 million	-3.6%
Grupo Aeroportuario del Centro (Nasdaq:OMAB)	$1.14 billion	-3.3%
Air (Nasdaq:AIRM)	$1.47 billion	-2.5%
Genesee & Wyoming (NYSE:GWR)	$3.51 billion	+2.1%
Grupo Aeroportuario del Sureste (NYSE:ASR)	$3.43 billion	-2.1%
Alaska Air Group (NYSE:ALK)	$3.16 billion	-1.5%

Broker Summary: OptionsXpress Online Trading Platform

American Railcar Industries (Nasdaq:ARII) has fallen 4.9% and is currently trading at $31.50 per share. The company is trading at a volume of 180,988 shares. At this rate, trading activity will likely be down from yesterday when 543,063 shares changed hands.

Slipping 3.6%, GulfMark Offshore (NYSE:GLF) is currently trading at $33.94 per share. So far today, the company's volume is 180,940 shares, 0.6 times the average daily volume.

After a decline of 3.3%, Grupo Aeroportuario del Centro (Nasdaq:OMAB) has hit a share price of $22.15. The company is currently trading a volume of 7,873 shares.

Air (Nasdaq:AIRM) has decreased to $110.97 per share, a 2.5% fall. The company's volume is currently 101,076 shares for the day, 0.3 times its current three-month average.

Genesee & Wyoming (NYSE:GWR) is up 2.1% to reach a current price of $76.55 per share. The company's volume for the day so far is 279,798 shares. Yesterday, volume was only 229,778 shares.

Falling 2.1%, Grupo Aeroportuario del Sureste (NYSE:ASR) is currently at a share price of $112.09. So far today, the company's volume is 17,768 shares, 0.2 times the current daily average.

At $44.24, Alaska Air Group (NYSE:ALK) has slipped 1.5%. This morning, the company is trading a volume of 427,976 shares.

The Bottom Line On any given day, a particular stock may see positive or negative change in its share price. Paying close attention to the previous ratios will help you identify key times to adjust your strategy. Tools like valuation ratios and profit margins, however, are only as useful as the context you put them in; remember to take historical data and competitor performance into account.