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 Accretive Health (NYSE: AH) got ill and fell as much as 16% today after the company released earnings.

So what: Revenue improved 30% this quarter, to $163.7 million, but fell just short of analyst estimates, which is weighing on shares. Profit was in line with expectations at $160,000, or $0.04 per share.

Now what: The earnings miss wasn't dramatic and the company reaffirmed full-year guidance in the range of $0.42 to $0.45. That's on the low end of estimates, but the 10% drop the stock is currently experiencing seems excessive. That said, I'm still not jumping into shares because the top end of guidance puts the stock at a hefty 58 P/E multiple for 2011 earnings.

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