The number of rigs actively exploring for oil and natural gas in the U.S. is up by six this week to 1,965.

Houston-based oilfield services company Baker Hughes Inc. reported Friday that 1,419 rigs were exploring for oil and 542 for gas. Four were listed as miscellaneous. A year ago, Baker Hughes reported 1,887 rigs.

Of the major oil- and gas-producing states, North Dakota gained four rigs, Pennsylvania added three and West Virginia, Oklahoma and Colorado were up one each.

Texas declined by two rigs and Alaska, Arkansas and New Mexico lost one each.

California, Louisiana, New Mexico and Wyoming were unchanged.