(Reuters) — U.S. drillers added oil rigs for a 10th week in a row, doubling the rig count in a 10-month recovery as energy companies boost spending on new production to take advantage of a recovery in crude prices.

Drillers added 21 oil rigs in the week to March 24, the biggest weekly increase since the week to Jan. 20, bringing the total count up to 652, up from a six-year low of 316 in May, energy services firm Baker Hughes Inc. said on Friday.

During the same week a year ago, there were 372 active oil rigs.

That rig count increase came despite a collapse in U.S. crude futures over the past two weeks down to levels seen when the Organization of the Petroleum Exporting Countries (OPEC) agreed to cut production on Nov. 30.

U.S. crude futures steadied around $48 a bbl on Friday as rising domestic production and inventories offset hopes OPEC output cuts were beginning to balance the global glut.