There's never a shortage of losers in the stock market.

Let's take a closer look at five of this past week's biggest sinkers.

Company

March 9 Weekly Loss My Watchlist
Oncothyreon (Nasdaq: ONTY) $5.04 (40%) Add
ZELTIQ Aesthetics (Nasdaq: ZLTQ) $6.70 (38%) Add
Green Mountain (Nasdaq: GMCR) $52.59 (23%) Add
Yelp (NYSE: YELP) $19.80 (19%) Add
Pandora (NYSE: P) $11.50 (17%) Add

Source: Barron's.

Oncothyreon was last week's biggest loser, shedding 40% of its value after revealing that clinical trial study results of its potentially promising lung cancer drug are still a year away.

ZELTIQ took a hit after posting a steep fourth-quarter loss and providing uninspiring guidance for 2012. The company's CoolSculpting machine uses intense cold to eradicate fat around the gut -- you know, beer handles -- that doesn't easily go away with diet or exercise.

Green Mountain felt more like a molehill after Starbucks unveiled its Verismo single-cup java brewing system. The high-pressure machine is more in line with espresso makers than Keurig's signature appliance, but the two companies that seemed to be budding partners last year may butt heads again this year.

I wasn't alone in predicting that shares of Yelp would cool off last week after a scorching IPO earlier this month. No one probably expected the local eatery reviews website to be the New York Stock Exchange's biggest loser.

Finally, Pandora got quieter after posting lackluster quarterly results. A wider-than-expected deficit and advertising revenue that failed to keep up with listener hours were enough to keep the leading music streaming website down.  

Ready for a bounce
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