The data from the EPA’s Greenhouse Gas Reporting Program show methane emissions from oil and natural gas production in the Barnett Shale of North Texas and the Permian Basin in West Texas have fallen over the past few years. Emissions also fell in East Texas and in the Anadarko Basin, which includes part of the Texas Panhandle.

In the Barnett Shale, methane emissions from oil and natural gas production fell by 180,000 metric tons of carbon dioxide equivalent (CO2eq) between 2011 and 2015, even as the number of facilities reporting data to the EPA increased by 10 percent.

In the Permian Basin, methane emissions fell by 600,000 metric tons CO2eq over the same period. The number of reporting facilities in the Permian also slightly increased.

EPA’s data sets for onshore oil and natural gas production are organized by basin. The Permian Basin is one of those regions. For the Barnett Shale, the most prominent counties are located in the Strawn Basin and the Fort Worth Syncline.

Four of the top ten natural gas producing counties in Texas are located in the Barnett Shale: Tarrant (the second largest producer overall), Johnson, Wise, and Denton. Five of the top ten oil producing counties are located in the Permian Basin, according to data from the Texas Railroad Commission.

Methane emissions from oil and natural gas production in East Texas also fell by about 100,000 metric tons CO2eq, although there was one fewer reporting facility in 2015 than in 2011. In the Anadarko Basin, which includes parts of the Texas Panhandle, western Oklahoma, and southwest Kansas, methane emissions declined by 2.7 million metric tons CO2eq.

Earlier this year, the EPA imposed new regulations on methane emissions from oil and natural gas activities, specifically on new or modified sites. The EPA claims the new rules are necessary to reduce methane emissions from petroleum and natural gas systems. The agency is now trying to finish additional regulations for existing well sites before President Obama leaves office in January 2017.

The Obama administration’s methane rules are part of a broader push by the White House to solidify its legacy on climate change. The EPA also says the rules are part of its efforts to develop a “clean energy economy.”