U.S. shale oil drillers have made big strides in adapting to lower crude prices by cutting costs and improving productivity, according to a report released Wednesday. American shale now makes up the bulk of about 9 million barrels a day of new oil that is commercially viable at long-term Brent oil prices averaging about $60 a barrel—more than at any point since 2009 and 1.5 million barrels of oil a day more than last year, said the report by energy consultancy Wood Mackenzie. Shale drillers have cut the costs of producing new supplies of oil by as much as 40% in the past two years by pushing for lower rates from the firms that provide equipment such as rigs, pipes and other services. The companies have also improved productivity at the wells themselves by […]