HOUSTON (AP) -- Oilfield services company Baker Hughes (BHI) says the number of rigs actively exploring for oil and natural gas in the U.S. dropped by one this week to 1,761.

The Houston-based company said in its weekly report Friday that 1,329 rigs were actively exploring for oil and 428 for gas. Four were listed as miscellaneous. A year ago, Baker Hughes counted 1,981 working rigs.

Of the major oil- and gas-producing states Pennsylvania gained six rigs, Texas rose by five, and Alaska, Arkansas, Colorado, and West Virginia each increased by one. Oklahoma lost nine rigs, North Dakota shed four, Wyoming decreased by two, and Louisiana and New Mexico each dropped one. California remained unchanged.

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