Oilfield services company Baker Hughes Inc. says the number of rigs exploring for oil and natural gas in the U.S. declined by 48 this week to 571.

The Houston firm said Friday 467 rigs sought oil and 104 explored for natural gas amid depressed energy prices. A year ago, 1,456 rigs were active.

Among major oil- and gas-producing states, Texas declined by 19 rigs; Oklahoma, eight; Louisiana, five; Pennsylvania, three; North Dakota, Utah and Wyoming, each two; and Ohio, one.

Alaska, Arkansas, California, Colorado, Kansas, New Mexico and West Virginia were all unchanged.