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

June 28

Weekly Loss

BlackBerry (BB -2.44%)

$10.45

24%

Barnes & Noble (BKS)

$15.96

16%

Kandi Technologies (KNDI 2.68%)

$5.71

15%

Diana Containerships (PSHG 1.99%)

$4.32

12%

Applied Micro (NASDAQ: AMCC)

$8.80

10%

Source: Barron's.

Let's start with BlackBerry. The smartphone pioneer tumbled on Friday after posting a quarterly loss. Analysts were holding out for a modest profit. 

It gets worse. BlackBerry moved just 100,000 PlayBooks during the quarter, making it unlikely to ever gain traction in the tablet market. BlackBerry also revealed that it shipped just 2.7 million smartphones running its updated BB 10 mobile operating system, a move that indicates it also isn't gaining enough traction in its flagship market.

Barnes & Noble is another company struggling to move tablets. The bookseller will discontinue the Nook Color tablet. Barnes & Noble will continue to sell the Nook e-reader, but clearly the transition from book superstore to consumer electronics has been rocky.

Kandi Technologies kicked off the week defending itself against a recent bearish article. Then the Chinese maker of electric vehicles diluted investors by executing a private placement with two institutional investors in a deal to raise $26.3 million in financing. 

Diana Containerships is shedding some of its cargo. Wells Fargo is downgrading the shipper from "outperform" to "market perform." Wells Fargo is also lowering its price target range to between $5 and $6. It was previously as high as $9.

Finally, we have Applied Micro taking a hit after its CFO announced his retirement. The market doesn't like when bean counters go away for any reason. Even an upbeat Raymond James analyst note -- suggesting that investors look beyond Applied Micro's CFO leaving -- failed to reverse the slide.

Ready for a bounce
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