Number of active U.S. drilling rigs up this week

HOUSTON, Sept. 8 (Xinhua) -- The number of active drilling rigs in the United States rose to 632 this week, up by one from the previous week but down by 127 from this time last year, according to the weekly data released Friday by Houston-based oilfield services company Baker Hughes.

These active drilling rigs included 513 oil rigs operating in U.S. oil fields, up by one from the previous week; 113 gas rigs, dow