NEW YORK (TheStreet) -- Plug Power (PLUG) continued lower on Tuesday. The stock has soared 982% in the past six months and 3,680% in the past 12 months before its starting a downward trend over the past week. Plug closed a week ago at $11.41, and on Tuesday was down 4.5% to $6.22
Zacks Equity Research calculated that 20.4% of the company's floating stock is sold short. Zacks rated Plug as a "buy," however, because of increased earnings estimates for the hydrogen fuel cell manufacturer.
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Plug isn't new to wild speculation and outsized expectations. The stock rose to more than $1,500 a share in the early 2000s only to fall as low as 13 cents in 2013.
The company saw a bump after last Thursday's fourth-quarter earnings release, in which the company reported a 2013 loss of $63 million on revenue of $27 million, but the stock has moved lower since.
Separately, TheStreet Ratings Team has this to say about its recommendation:
"We rate PLUG POWER INC (PLUG) a SELL. This is driven by several weaknesses, which we believe should have a greater impact than any strengths, and could make it more difficult for investors to achieve positive results compared to most of the stocks we cover. The company's weaknesses can be seen in multiple areas, such as its deteriorating net income and weak operating cash flow."