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: Investors were spitting out shares of BJ's Restaurants (BJRI 2.58%) today, as the stock fell as much as 19%, after a poor earnings report.

So what: The stock hit its lowest point in two years today, as it received two ratings downgrades after posting an EPS of just $0.24, on expectations of $0.28. Revenue grew 16% to $175.2 million, but also fell below estimates. The miss seems to indicate slowing growth and reflects an industry trend, as a number of other restaurants have delivered disappointing results. Same-store sales increased just 2.3%, as management blamed "very challenging headwinds in the casual dining segment during the quarter."

Now what: With net income increasing just 8% in the quarter, this growth story may be petering out. BJ's managed to open four new restaurants in the quarter, increasing its store base by about 3%, but the sluggish same-store sales indicate that growth may continue to be slow. With a P/E around 27 and no apparent competitive advantage, I see little reason to invest.

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