December's oil output from Alaska's giant fields on the North Slope slid 6.5 percent compared to a year earlier as output from existing wells continues to erode, according to Bloomberg.
Some 582,150 barrels a day were produced in December. A year ago, the output was 622,355 barrels a day. However, this year's output was about 200 barrels a day more than it was in November.
"In total, we're not seeing enough new production to offset the natural declining rates of production from existing wells," Ed King, petroleum economist for Alaska's tax division in Anchorage, told Bloomberg. The North Slope output has declined every year since 2002.
Refineries on the West Coast are increasingly depending on imports and rail shipments from the Midwest instead of North Slope crude.