SINGAPORE (AP) — After surging above $51 a barrel the previous day, oil prices drifted back Friday in Asia as traders reevaluated expectations for renewed crude demand amid persistent uncertainty about the global economy.

Benchmark crude for April delivery fell 67 cents to $50.94 a barrel by afternoon in Singapore on the New York Mercantile Exchange. Prices climbed $3.47 on Thursday to settle at $51.61.

With the April contract set to expire Friday, most of the trading had shifted to the contract for May, which was down 37 cents to $51.67.

Oil prices have jumped from below $35 a barrel last month amid a global stock market rally and easing concerns about the international financial sector.

But oil inventories continue to rise, and there’s been scant solid evidence that the fall in crude demand has bottomed. The outlook for the global economy also remains cloudy.