U.S. drillers add the most oil rigs since April 2013 -Baker Hughes

Jan 20 (Reuters) - U.S. energy companies this week added the most oil rigs in nearly four years, extending an eight-month recovery as drillers take advantage of a deal by OPEC to cut supplies that has boosted prices over $50 a barrel since early December. Drillers added 29 oil rigs in the week to Jan. 20, bringing the total count up to 551, the most since November 2015, energy services firm Baker Hughes Inc said on Friday. During the same week a year ago, there wer