HOUSTON, Nov. 22 (Xinhua) -- The number of active drilling rigs in the United States fell to 583 this week, down by one from the previous week and by 39 from a year ago, according to the weekly data released Friday by Houston-based oilfield services company Baker Hughes.
These active drilling rigs include 479 oil rigs operating in the U.S. oil fields, up by one from the previous week; 99 gas drilling rigs, down
