Pioneer Natural Resources (PXD -2.28%) stock has gone up nearly 600% in just the past five years. That has crushed the market, which is up just over 92% over that same time period. Despite the market-crushing returns, there's still a lot of fuel left in Pioneer Natural Resources' tank. Here are three reasons why the stock could continue to rise.

It's sitting on nearly 10 billion barrels of recoverable oil and gas

Pioneer Natural Resources believes that it is sitting on the biggest oil field ever discovered in the U.S. The company sees the Spraberry and Wolfcamp formations within the Permian Basin holding economically recoverable resources totaling 75 billion barrels of oil equivalent, or BOE. That is more than double the size of the Eagle Ford shale. Given Pioneer Natural Resources' large acreage position in the play, it believes it can economically recover nearly 10 billion BOE.

The key for the company will be to prove it can recover this oil and gas. In order to do that, Pioneer Natural Resources needs to continue drilling wells and gathering the data that proves just how much oil and gas can be recovered. This data provides certainty as the oil and gas moves from economically recoverable resources to proved reserves, as noted in the chart below.

Source: U.S. Energy Information Administration  

Investors place more value on proved reserves because of the certainty that these do in fact exist and can be economically produced. As of the end of last year Pioneer Natural Resources had 845 million BOE in proved reserves, but just 423 million BOE in the Spraberry and Wolfcamp formations, as noted on the chart on the left-hand side of the following slide.

Source: Pioneer Natural Resources Investor Presentation. 

The company believes that through 2016 it can add more than 600 million BOE in proved reserves in these two formations. As these resources move to proved reserves the stock could rise due to the added certainty that the company will indeed produce this valuable oil and gas.

Moving from exploration and appraisal to development

This year is a transitional one for Pioneer Natural Resources, as it's moving from horizontally appraising the Spraberry and Wolfcamp formations to developing them. The transition will see the company spend less money on science to understand the rocks and more money on drilling wells that increase production and prove its reserves. Further, the company is now starting to transfer the knowledge and expertise it gained in the Eagle Ford shale to the Spraberry and Wolfcamp.

Source: Pioneer Natural Resources Investor Presentation. 

This transition will make Pioneer Natural Resources a better operator. As it improves its operations it can better stretch its capital dollars, which will earn higher returns for investors. Better returns and improved profitability tend to move stocks higher.

Pushing to end the oil export ban

Pioneer Natural Resources and its fellow independent oil and gas peers are pushing for the U.S. to end its more than 40 year ban on oil exports. The reason it wants the export ban lifted is because the production of light crude oil in the U.S. is growing so fast that our refineries can't keep up. This is causing the price of domestically produced crude oil, which is commonly benchmarked to WTI, to trade at a discount to the globally benchmarked Brent crude oil. As the following slide shows, the two used to trade around the same price -- but as U.S. oil production surged it has caused WTI oil to trade at a discount.

Source: Pioneer Natural Resources Investor Presentation. 

Pioneer Natural Resources believes that by ending the oil export ban its oil will fetch a higher price, which will improve profits. This will also allow the company to then drill more wells, which will push U.S. oil production even higher and create more jobs, putting more tax revenue into the government's pockets and even pushing the price of gasoline down. If the industry is successful in convincing Congress to end the export ban it could lift the stock of Pioneer Natural Resources and its U.S.-focused peers.

Investor takeaway

Pioneer Natural Resources stock has been a strong performer over the past few years. Given the massive resource base it's sitting on, which it's just starting to develop, along with possible upside from the lifting of the crude oil export ban, there is plenty of reason to believe it will continue its bull run.