Proved reserves of natural gas in the United States finished at 388.8 Tcf in 2014, setting a record high for the second consecutive year, the Energy Information Administration (EIA) said in a report published Monday.

U.S. crude oil reserves also rose in 2014, for the sixth consecutive year, exceeding 39 billion bbl for the first time since 1972, the EIA said.

Natural gas reserves increased 9.8% in 2014, up from 354 Tcf at the end of 2013, while crude oil reserves increased 9.3% year/year, to 39.9 billion bbl from 36.5 billion bbl in 2013.

U.S. shale plays accounted for just over half of total natural gas proved reserves in 2014 at 199.7 Tcf. The Marcellus Shale grew the most in 2014, adding 22.1 Tcf to finish at 84.5 Tcf in proved reserves, up from 62.4 Tcf in 2013. The Eagle Ford (6.3 Tcf), Woodford (4.1 Tcf) and Utica (4.1 Tcf) shales also added reserves in 2014.

The Barnett Shale’s proved natural gas reserves fell by 1.7 Tcf in 2014, while the Haynesville (plus 500 Bcf) and Fayetteville shales (minus 500 Bcf) saw modest changes.

U.S. tight oil plays added 3.3 billion bbl in proved reserves in 2014, with the Bakken/Three Forks (1.13 billion bbl) and the Eagle Ford (995 million bbl) showing the biggest gains. The Bone Spring/Wolfcamp (387 million bbl), the Niobrara (495 million bbl) and the Marcellus (143 million bbl) also added crude oil reserves in 2014, while the Barnett’s proved reserves declined by 11 million bbl.

At the state level, Pennsylvania saw the biggest increase in proved natural gas reserves, adding 10.4 Tcf in 2014, while Texas was the biggest mover in crude oil reserves, adding just over 2 billion bbl. Pennsylvania still finished second to Texas in total natural gas reserves in 2014, while West Virginia passed Wyoming and Colorado to become the fourth-largest natural gas reserves state.

The EIA said it doesn’t expect 2014’s gains in proved reserves to continue, given the low commodity price environment that has constrained the industry in 2015.

“Sustained low prices for oil and natural gas are anticipated to reduce the reserves in EIA’s next report (for year-end 2015),” EIA said. “Lower prices have curtailed drilling and made recovery economics more challenging. Although resource estimates are not necessarily reduced by lower prices, the calculation of proved reserves is sensitive to price.”