Newfield Exploration (NYSE:NFX) has seen its stock rise almost 75% this year. That's a huge run-up in a short period of time driven by investors starting to appreciate the silver lining of the company's transformation efforts. However, the price advance sparks the questions: Since there's only a little more work to do on the corporate makeover, is Newfield still worth buying?

Big expectations

Over the last five years or so, Newfield Exploration has sold roughly $2 billion of non-core assets. This included drilling programs in the Gulf of Mexico and Malaysia, as well as non-core domestic plays. Although these sales have refocused the energy and exploration company around four land-locked U.S. regions, it hints at a history of big dreams. In fact, one of Newfield's remaining assets for sale is in China. Clearly, the company held global aspirations at one time.

So, for investors who were enamored of that dream, the asset sell-off must have been a bitter pill. And that helps explain some of the volatility in the shares over the past decade after what had been a fairly steady rise. That said, the heavy lifting of the corporate makeover is now behind Newfield Exploration.

NFX Chart

NFX data by YCharts.

Today, the company is as much an oil driller as a gas driller, with a roughly 50/50 split. And it has embraced the U.S. energy Renaissance, removing the political and environmental risks of drilling in foreign countries (Malaysia and China) and inhospitable environments (the open sea, for example). These changes, coupled with a hedging program, should make Newfield's top and bottom lines much more reliable. Results will still be subject to the vagaries of oil and gas prices, not to mention drilling success or failure, but management has really de-risked its business model.

Where do we go from here?

So, that helps explain why the shares have had such a healthy run of late. But where does that leave investors? Is it time to sit tight, buy more, or get out? With only the Chinese asset remaining to be sold, once some recent drilling troubles are cleared up, the corporate transformation will be largely complete. If the makeover was why you bought the company, you should at least be considering selling.

If you were looking for an up-and-coming domestic oil and gas play, holding tight or buying more isn't a bad idea -- if you have a strong stomach. While the stock is up notably, Newfield's price to book value is 1.8, in line with its five-year average and a touch below the industry average of around 2. So, its pricing isn't out of line with its peers. And there's still the upside from the Chinese asset sale that will help the company pay off debt and/or expand in core regions. The big story has largely been priced in, but it hasn't fully played out just yet.

Source: Public domain, via Wikimedia Commons.

That said, you'll need to keep a close eye on drilling performance. That's going to increasingly be the main driver of Newfield's results going forward. And so far, it's looking pretty good. Management expects production to increase around 28% a year through to 2016. And new wells have been meeting or exceeding expectations. If the driller keeps that up, there's no reason to expect a steep share price decline unless oil and gas prices nosedive, which would impact the entire industry, and Newfield's hedges will help soften the blow, anyway.

For the aggressive investor in you

There's no denying the excitement around hydraulic fracturing in U.S. shale regions. And Newfield Exploration is right in the thick of this trend after years of buying and selling assets. With a healthy mix of oil and gas, and a currently successful drilling program, Newfield looks like it should continue to benefit from the U.S. energy renaissance. Priced in line with its peers, there's still reason to like the company's shares. However, after a big run-up, it's probably most appropriate for more aggressive investors.

Reuben Brewer has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. 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 Motley Fool has a disclosure policy.