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

Jan. 13 Weekly Loss My Watchlist
Metabloix (Nasdaq: MBLX) $2.54 51% Add
WebMD (Nasdaq: WBMD) $27.76 27% Add
hhgregg (NYSE: HGG) $10.68 23% Add
Complete Genomics (Nasdaq: GNOM) $2.86 23% Add
Camelot Info Systems (NYSE: CIS) $2.18 22% Add

Source: Barron's.

Metabolix was the market's biggest loser, shedding a little more than half of its value after Archer Daniels Midland backed out of a joint venture for biodegradable plastics.

WebMD called in sick with several different maladies. The medical-website operator announced that its CEO is leaving the company, it was no longer considering a sale of the company, and its outlook for 2012 is looking rather weak.

Shares of hhgregg laid an egg, after the consumer-electronics retailer hosed down its near-term prospects. The chain specializing in big-ticket appliances and gadgetry now is looking to earn no more than $1.15 a share this fiscal year. Its earlier outlook was calling for profitability per share to come in between $1.26 and $1.41.

Complete Genomics was one of the market's biggest winners the prior week, but shares of the genetics specialist went the wrong way this time around after Oppenheimer & Co. downgraded the stock.

Finally we have Camelotgetting lanced a lot, as class action attorneys continue to file lawsuits against the Chinese IT services provider, alleging that Camelot made misleading financial statements before the stock began crashing last year.

It was a rough week for these five stocks. If you want to shake yesterday's losers and ride tomorrow's winners, a new special report reveals The Motley Fool's top stock for 2012. It's free, but only for a limited time, so check it out now.

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