UPDATE 1-U.S. drillers add oil rigs for 18th week in a row -Baker Hughes

(Adds rig count from same week last year) May 19 (Reuters) - U.S. energy companies added oil rigs for an 18th week in a row, the second-longest such streak on record, as expectations of higher crude prices have motivated drillers to boost monthly shale production to its highest level since mid-2015. Drillers added eight oil rigs in the week to May 19, bringing the total count to 720, the most since April 2015, energy services firm Baker Hughes Inc said on Friday. <RIG-OL-USA-