In talking about companies like Nabors (NYSE:NBR), Transocean (NYSE:RIG), and so on, I've made vague references to sharing in the pain of investors in the drilling space. Well, now you know why -- I own shares in Patterson-UTI Energy (NASDAQ:PTEN), a riskier-than-average driller that got absolutely pounded from February until very recently.

As with other drillers, this punishment didn't result from poor near-term prospects. Revenue in the company's fourth quarter jumped 84% and operating income nearly quintupled. Growth was fueled by continued strength in the contract drilling business as well as strong results in other units like pressure pumping, fluids, and oil/gas production.

Looking at that drilling business, we see that Patterson's utilization climbed from 63% to 72%, and that average revenue per day rose 53% annually and 11% from the third quarter to more than $17,000. As the higher utilization rate may suggest, Patterson put more rigs into the field this quarter, averaging 292 per day versus 283 in the third quarter.

And like other drillers, Patterson is also expecting business to continue to improve for the immediate future. The company is looking to put eight more rigs into service next quarter, and it expects dayrates to rise another $1,000.

Now, let's be clear about something with Patterson. This is not a widows-and-orphans stock. The company does a lot of its business with small natural gas exploration and production companies, and only about 15% of its business is on long-term (longer than one year) deals. That makes it more sensitive than average to gas prices; a major client like ExxonMobil (NYSE:XOM) may swallow some momentary negative price swings and press ahead with drilling plans even if gas prices fall, but smaller clients don't always have that same luxury.

Investors also need to be aware of the embezzlement alleged here. The former chief financial officer is charged with dipping his hand into the till to the tune of about $78 million over seven years. The good news, though, is that the company is aggressively trying to recover this money (though it won't get all of it), and I'd be willing to bet that its internal controls are now significantly stronger than average. (As the saying goes, there are none so religious as the recently converted.)

Even though this stock has been a bit of a white-knuckle experience at times, I'm hanging on. Keep in mind, though, that this is part of a more diverse group of energy-related companies that I own (including a major producer, an infrastructure company, and a coal technology company). I still think natural gas can go up from here, but this isn't the sort of stock in which to invest your entire nest egg.

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Fool contributor Stephen Simpson owns shares of Patterson-UTI, but has no financial interest in any other stocks mentioned (that means he's neither long nor short the shares).