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 Insituform Technologies (Nasdaq: INSU) have tanked today, falling 10% after the company updated guidance.

So what: Management updated third-quarter earnings guidance to $0.25 to $0.27 per share, falling well below the $0.43 analysts were expecting. For the full year, management sees earnings per share of $0.90 to $1.00, also below estimates of $1.18 per share.

Now what: The North American sewer rehabilitation business has been hit especially hard this year by delays and smaller-than-expected projects. However, management has reorganized the company to cope with these challenges. The news is disappointing, but the company is still profitable and expects conditions to improve going forward. I wouldn't start to panic based on today's news.

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Fool contributor Travis Hoium does not have a position in any company mentioned. You can follow Travis on Twitter at @FlushDrawFool, check out his personal stock holdings or follow his CAPS picks at TMFFlushDraw.

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