Can you believe that we are several years into the shale boom already? For the past three years, investors have all been in love with production growth and making operations more efficient. Today, though, companies need to start thinking about generating cash. Cabot Oil & Gas (NYSE:COG), Range Resources (NYSE:RRC), and Southwestern Energy (NYSE:SWN) have made their hay as some of the best pure natural gas producers in the country, but how have they performed when it comes to funding that production without tapping the debt markets. 

One way investors can take a better look at this is to see how much of its capital expenditures are covered by operational cash flow and how that has changed over time. Find out how Cabot, Range, and Southwestern have done over the past couple years at closing the funding gap by tuning into the video below.

America's $600 billion energy problem means invest in these three stocks today
A dark specter is looming that is ready to stop America's Energy boom right in its tracks, and no one is talking about it. This one critical element could cost us over $600 billion, but every day we wait that number grows and grows. The U.S. government thinks investment in this sector is so important, even the Internal Revenue Service will give you a free pass if you invest in this select group of stocks. Our analysts at The Motley Fool have combed over this special class of stocks and we have identified three that could make you rich! Find out the names of these IRS-gift-wrapped stocks in our special report "3 Stocks The IRS Is Begging You to Buy." Simply click here and we'll give you free access to this valuable investing resource. 

Tyler Crowe has no position in any stocks mentioned. You can follow him at under the handle TMFDirtyBird, on Google+, or on Twitter @TylerCroweFool.

The Motley Fool recommends Range Resources. The Motley Fool owns shares of EOG Resources. 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.