Many S & P 500 stocks turned in stellar performances in 2011, despite the flat performance of the overall index during the year. These top outperformers for the year were led by stocks in the energy and health care sectors. (For more, see Earning Forecasts: A Primer.)

Investopedia Markets: Explore the best one-stop source for financial news, quotes and insights.

The Winners
Cabot Oil & Gas (NYSE:COG) was the best performing stock in the S & P 500 in 2011, moving up 100.1% for the year. Cabot Oil & Gas continued to increase development of oily assets during the year and maintained its lead as one of the premier operators in the Marcellus Shale. The company also raised production guidance mid year and expects this growth to continue in 2012.

El Paso (NYSE:EP) was second on the list and moved 93% higher in 2011. The company achieved this performance the old fashioned way, with a buyout offer from Kinder Morgan (NYSE:KMI) at a large premium. The deal will create the largest midstream company in the United States, with 80,000 miles of pipeline under operation.

The deal also put a large amount of oil and gas properties into the marketplace as the combined company has put El Paso's exploration and production assets up for sale, as it doesn't plan on staying in the upstream business.

El Paso is now marketing 4 Tcfe of proved oil and gas reserves with production of approximately 840 million cubic feet of natural gas equivalents per day. The company also has considerable undeveloped acreage, as well, to offer to potential buyers.

Growth is the story for Intuitive Surgical (Nasdaq:ISRG), which moved up 80% in 2011. The company began 2011 with revenue growth guidance in a range from 16 to 20%, but by midyear had moved that growth up to a range from 19 to 21%. Intuitive Surgical wasn't finished, however, and by the end of 2011 the company increased it yet again to a range from 22 to 23%.

Intuitive Surgical has also beaten consensus earnings estimates for the last four quarters, usually by a wide margin, delighting investors and moving the stock higher.

MasterCard (NYSE:MA) is also an impressive growth story with strong earnings momentum, and has reported results above consensus earnings estimates for the last four quarters.

MasterCard has seen a surge in volume and processed transactions in 2011 as global use of its services increase. The stock also benefited from a midyear regulatory decision by the Federal Reserve to increase the proposed cap on debit card fees. MasterCard gained 67% in 2011.

Biogen (Nasdaq:BIIB) ended 2011 up by 64%, as the company reported positive news during the year on its pipeline of drug candidates. Much of the gain during the year was due to optimism on BG-12, an experimental drug used to treat multiple sclerosis. Analysts expect the drug to become a leading treatment for multiple sclerosis, with peak annual sales estimated at $3 billion.

The Bottom Line
Although price volatility soared in 2011 as investors shifted their mood on the global economy almost daily, the S & P 500 index ended the year with no gain. This was not the entire story in 2011, as many stocks did much better than the overall indexes, rewarding investors who didn't give in to fear. (For additional reading, check out 5 Must-Have Metrics For Value Investors.)

Use the Investopedia Stock Simulator to trade the stocks mentioned in this stock analysis, risk free!

At the time of writing, Eric Fox did not own shares in any of the companies mentioned in this article.