China Petroleum & Chemical Corp Among Energy's Biggest Movers on November 27, 2012

It's been a bad day for the market after the morning's trading. The Nasdaq has decreased 0.2%; the S&P 500 has declined 0.2%; and the Dow has fallen 0.3%. The energy sector is the category of stocks that relate to producing or supplying energy. This sector includes companies involved in the exploration and development of oil or gas reserves, oil and gas drilling, or integrated power firms. Performance in the sector is largely driven by the supply and demand for worldwide energy. Energy producers will do very well during times of high oil and gas prices, but will earn less when the value of energy drops. Furthermore, this sector is sensitive to political events, which historically have driven changes in the price of oil.

The Energy sector (XLE) is currently lagging behind the overall market, down 0.5%, and its current biggest movers are:

Company	Market Cap	Percentage Change
Mcmoran (NYSE:MMR)	$2.02 billion	-16%
PDC Energy (Nasdaq:PDCE)	$953 million	+4.4%
W&T Offshore (NYSE:WTI)	$1.23 billion	+3.4%
Rowan Companies (NYSE:RDC)	$4.09 billion	-3%
Ocean Rig UDW (Nasdaq:ORIG)	$2.09 billion	+2.8%
TransMontaigne Partners (NYSE:TLP)	$503.1 million	+2%
China Petroleum & Chemical Corp (NYSE:SNP)	$94.23 billion	-2%

Broker Summary: OptionsXpress Online Trading Platform

Mcmoran (NYSE:MMR) is at a share price of $8.11 after a sharp decline of 16%. So far today, the company's volume is 19.4 million shares.

PDC Energy (Nasdaq:PDCE) has risen 4.4% and is currently trading at $32.86 per share. The company's volume is currently 221,573 shares for the day, in line with the current daily average.

W&T Offshore (NYSE:WTI) is currently trading at $16.60 per share, a 3.4% increase. So far today, the company's volume is 246,829 shares.

Rowan Companies (NYSE:RDC) has decreased to $31.19 per share, a 3% fall. So far today, the company's volume is 976,895 shares, 0.6 times its current three-month average.

After an increase of 2.8%, Ocean Rig UDW (Nasdaq:ORIG) has reached a current price of $16.30. The company's volume for the day so far is 48,856 shares.

TransMontaigne Partners (NYSE:TLP) has increased to a share price of $35.01, a 2% rise. At 2,921 shares, the company's volume so far today is 0.1 times the current daily average.

China Petroleum & Chemical Corp (NYSE:SNP) has fallen 2% and is currently trading at $104.68 per share. So far today, 21,305 shares of the company's stock have changed hands. This is on pace to reach yesterday's trading volume of 50,348 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.