Investing.com - U.S. commercial crude oil inventories (excluding those in the Strategic Petroleum Reserve) rose by 4.7 million barrels last week, versus expectations for a decline of nearly 600,000 barrels, the Energy Information Administration said Wednesday.
In the previous week, crude inventories rose by 5.4 million barrels.
The second-straight weekly build of around 5 million barrels or so seemed largely due to weak refining activity, unusual for this time of year when gasoline makers would typically be running at full pace and pushing out as much of the motor fuel as possible in anticipation of a demand surge for the peak summer driving season.
Refineries operated at 89.9% of their operable capacity last week, the EIA said. The norm for this time of year would be at least 90%.
The EIA also said that total motor gasoline stockpiles increased by 3.7 million barrels during the week ended May 17, against forecasts for a drop of nearly 816,000. In the earlier week to May 10, gasoline inventories fell by 1.1 million barrels.
Distillate fuel inventories rose by 800,000 barrels last week versus expectations for a drop of 48,000 barrels. In the previous week, distillate stockpiles rose by 84,000 barrels.
Gasoline production decreased last week, averaging 9.9 million barrels per day, the EIA said. Distillate fuel production decreased last week, averaging 5.2 million bpd.
Oil prices slumped on the weekly EIA data.
West Texas Intermediate futures, the benchmark for U.S. crude, was down $1.36 , or 2.2%, at $61.77 per barrel by 111:13 AM ET (15:13 GMT).
London Brent futures, the global benchmark for oil, slipped by $1.07, or 1.5%, to $71.11.
"Despite a chunky drop in imports, refinery runs below year-ago levels have encouraged a second-consecutive build to crude inventories," said Matthew Smith, analyst at New York-based crude cargo tracker Clipperdata.
"Crude inventories (are) now up over 37 million barrels, or 8.5% percent, in the last nine weeks," Smith added.
John Kilduff, founding partner at New York energy hedge fund Again Capital, also noted that despite imports falling by nearly 700,000 barrels to 6.9 million, there was a build of 1.3 million barrels at the Cushing, Okla. delivery point for U.S. crude.
"The rise in crude oil inventories was punctuated by a large jump in barrels stored at the Cushing delivery hub and the overall rise came despite a sizeable drop in imports on the week," Kilduff said.