By the Numbers

The Best and Worst Performing IPOs of 2011

GNC Storefront
Photo: Bloomberg via Getty Images

Despite a strong start in the first half of the year, the initial public offering market has slowed as more companies delayed their offerings due to uncertainties in the global economy. 

A total of 125 companies made their stock market debut this year, compared with 153 in 2010, 63 in 2009, 31 in 2008, during the financial crisis, and 214 in 2007.

Although technology and energy make up 57 percent of the deals this year, the most successful IPO, based on price appreciation, is GNC, a nutritional-product retailer that went public back in April for $16 a share and is up nearly 75 percent since then.

The second-best performing IPO is Tesoro Logistics, a subsidiary of oil refiner Tesoro , followed by Imperva, a data-security software firm. Both companies are up more than 50 percent from their initial filing prices. 

The title of worst-performing IPO in 2011 belongs to FriendFinder Networks, the publisher of Penthouse, which is down more than 94 percent from its filing price of $10 per share back in May.

Imperial Holdings, a specialty finance company, is the second-worst IPO this year. A class action suit was filed Dec. 14 in connection with its IPO, and its stock has lost nearly 83 percent of its value since its filing price of $10.75 back in February.

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