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What: Shares of energy-services company Key Energy Services (NYSE: KEG) jumped as much as 19% in intraday trading after the company announced first-quarter results.

So what: On a GAAP basis, Key Energy's first-quarter earnings were in the red, registering a $0.13 per-share loss. However, that loss was driven by a loss on the company's debt refinancing. Excluding that expense, Key Energy showed earnings per share of $0.09, topping the $0.07 that analysts had expected. Revenue for the quarter increased 12% from last year to $391 million.

Now what: Management's guidance was also very positive. Citing an "improving outlook," CEO Dick Alario projected full-year 2011 revenue to be up 50% to 55%. He also expects that second-quarter revenue will be up 15% to 20% sequentially and earnings per share will fall in a range of $0.18 to $0.21. The EPS guidance easily tops the current Wall Street expectation of $0.14 for the quarter.

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Fool contributor Matt Koppenheffer does not have a financial interest in any of the companies mentioned. You can check out what Matt is keeping an eye on by visiting his CAPS portfolio, or you can follow Matt on Twitter @KoppTheFool or on his RSS feed. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Fool’s disclosure policy prefers dividends over a sharp stick in the eye.