Oilfield services company Baker Hughes Inc. says the number of rigs actively exploring for oil and natural gas in the U.S. decreased by four this week to 1,739.

The Houston-based company said in its weekly report Friday that 1,361 rigs were exploring for oil and 372 for gas. Six were listed as miscellaneous. A year ago there were 1,839 active rigs.

Of the major oil- and gas-producing states, Colorado gained three rigs and Louisiana, North Dakota and West Virginia each gained one.

Texas lost five rigs, Ohio and Oklahoma each lost two and Arkansas, Kansas and Pennsylvania each lost one. Alaska, California New Mexico, Utah and Wyoming were unchanged.