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 15 this week to 1,873.

The Houston firm said in its weekly report Friday that 1,558 rigs were exploring for oil and 314 for gas. One was listed as miscellaneous. A year ago there were 1,748 active rigs.

Of the major oil- and gas-producing states, Oklahoma gained eight rigs, Pennsylvania gained two and Alaska, California, Colorado, North Dakota and Ohio each gained one.

Kansas lost three rigs while Louisiana lost two.

Arkansas, New Mexico, Texas, Utah, West Virginia and Wyoming were unchanged.

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

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