The figure reflects a huge surge in U.S. oil drilling, up nearly 60% in the past year and the highest total since at least 1987, when oil services company Baker Hughes Inc. began keeping track.The drilling boom is being driven by a variety of factors. New technologies have allowed companies to tap vast new oil reserves in places like North Dakota, Texas and, most recently, Ohio. High oil prices are making once-unprofitable fields more tempting. And low natural-gas prices are leading companies to shift their focus to finding oil. Natural-gas drilling, which generally uses the same rigs but in different places, is down 8% in the past year.
All that drilling is helping to boost U.S. oil production. The U.S. pumped 3.9 million barrels a day from onshore fields in March, up 5.9% from a year earlier and the most in nearly a decade.
