Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of shoemaker Deckers Outdoor (Nasdaq: DECK) plummeted 25% today after its quarterly results and guidance fell well below Wall Street estimates.

So what: Deckers' first-quarter revenue squeaked by estimates, but a brutal bottom line -- EPS fell 59% to $0.20 versus the consensus of $0.25 -- confirms huge worries over its profitability. Management blamed the mild winter for weak sales of its UGG boots, but spiking sheepskin costs are now becoming a long-term concern for investors.   

Now what: Management now expects earnings to drop 9%-10% in 2012, implying EPS of $4.56-$4.61, which was also well below Wall Street's view of $5.17. "We're managing this business for the long term," CEO Angel Martinez reassured analysts in a conference call, "and I'm very confident that the growth strategies we've developed for our brand portfolio are intact." More important, with the stock now off a whopping 55% from its October highs and trading at a single-digit forward P/E, buying into that optimism won't cost much.  

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