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 Alpha Natural Resources (NASDAQOTH:ANRZQ) jumped as much as 17% today, after releasing earnings.

So what: Fourth quarter revenue fell 25%, to $1.56 billion, and net loss was $128 million, or $0.58 per share. But on an adjusted basis, which pulls out one-time items, the loss was just $0.19 per share, well ahead of the $0.55 loss that Wall Street expected.  

Now what: It's not exactly good when you lose $128 million, but when Wall Street expects worse, your stock can shoot higher. Still, I would focus on how poorly Alpha Natural is doing instead of just looking at expectations. Coal producers are dealing with low prices and are playing a game of chicken to see how they survive until the market recovers. That's a game I don't want to play, so I'm certainly not buying this earnings report today.

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