(Bloomberg) -- Oil producers still reeling from the late-2018 price collapse shut down U.S. drilling rigs at the fastest pace in almost three years.

The number of working oil rigs fell by 21 this week to 852, according to data released Friday by oilfield-services provider Baker Hughes. The tally has drifted lower since reaching a 3 1/2-year high in mid-November.

Although crude futures have surged more than 25 percent since Christmas Eve, oil explorers are reluctant to expand activity without more concrete signals that the recovery will endure. In fact, the rig fleet may continue to shrink, according to Colin Davies, an analyst at Sanford C. Bernstein & Co.

“Drilling rigs have remained relatively resilient” through market gyrations, Davies wrote in a note to clients before Friday’s report. “Drillers will begin to get more scrutiny as rig count flattens and begins to fall.”’

Oil production in the U.S. rose to a record 11.9 million barrels a day last week, according to the Energy Information Administration.

To contact the reporter on this story: Austin Weinstein in New York at aweinstein18@bloomberg.net

To contact the editors responsible for this story: Simon Casey at scasey4@bloomberg.net, Joe Carroll

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