HOUSTON (AP) — Oilfield services company Baker Hughes Inc. says the number of rigs exploring for oil and natural gas in the U.S. rose by one this week to 1,875.

The Houston firm said in its weekly report Thursday that 1,563 rigs were exploring for oil and 311 for gas. One was listed as miscellaneous. A year ago there were 1,759 active rigs.

Of the major oil- and gas-producing states, Alaska, Kansas, Louisiana, Pennsylvania and Texas gained two rigs each. North Dakota, Ohio and Wyoming each gained a rig.

Oklahoma lost 11 rigs, while California and West Virginia lost one each. Arkansas, Colorado, New Mexico and Utah had unchanged rig counts.

The U.S. rig count peaked at 4,530 in 1981 and bottomed at 488 in 1999.

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