The EIA’s oil-production estimates are based on the number of drilling rigs in different plays and calculations of how productive each piece of equipment is. The number of rigs drilling for oil fell to 922 on Friday, according to oilfield service company Baker Hughes Inc. Oil rigs in the U.S. peaked in October at 1,609. To contact the reporter on this story: Dan Murtaugh in Houston at [email protected] To contact the editors responsible for this story: David Marino at [email protected] Richard Stubbe