In the early 2000s, West Virginia has been a major producer of natural gas, with wells in nearly every county west of the Allegheny Front. Most are shallow, but deeper wells, like those in the Oriskany and Ordovician layers, need more money and advanced tools. Since 2010, gas production has grown ten times, mostly from shale wells. The state annually generates about 3.2 trillion cubic feet of natural gas, making it the fifth largest producer in the U.S., accounting for about 7.6% of all domestic production.