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

April 20 Weekly Loss My Watchlist
Firsthand Technology Value (Nasdaq: SVVC) $26.50 (28%) Add
Arena Pharmaceuticals (Nasdaq: ARNA) $2.17 (25%) Add
Tempur-Pedic (NYSE: TPX) $66.53 (23%) Add
Riverbed Technology (Nasdaq: RVBD) $19.85 (22%) Add
Clearwire (Nasdaq: CLWR) $1.67 (21%) Add

Source: Barron's.

Firsthand Technology Value Fund -- a closed-end fund that took off earlier this year after snapping up shares of Facebook -- tumbled after pricing a secondary offering at a deep discount to its market price. Firsthand also revealed that its net asset value was a lot lower than its market price. It was easy to see this tumble coming.

There was no material news driving shares of Arena Pharmaceuticals lower. The company's potentially promising obesity drug is still a couple of weeks away from its next regulatory hurdle. However, after seeing its stock soar 73% last month, a correction is perfectly natural in this competitive niche.

Tempur-Pedic wasn't as crowd-pleasing as its premium mattresses after posting uninspiring guidance for the entire year. Tempur-Pedic's outlook for net income to fall within a range of $3.80 a share to $3.95 a share is short of the $3.97 a share that analysts were expecting.

Riverbed Technology took a hit after posting quarterly results that came in on the low end of already-soft guidance. The network optimization specialist's guidance for the current quarter is also below where the pros were perched.

Clearwire disconnected with investors after Verizon Wireless moved to sell some of its wireless spectrum, a move that may introduce more competition to the already debt-saddled company.

Ready for a bounce
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