Crude oil prices gained $1.66 Friday to $50.36 per barrel, but the four-month slide that began in July has been precipitous. Crude oil peaked above $147 per barrel on July 11.

Heating oil prices rose 0.0324 cents to $1.7005 per gallon Friday. Reformulated blendstock gasoline rose 0.0729 cents to $1.065 per gallon. Natural gas prices rose 0.206 cents to $6.51 per million British thermal units.

At the pump, the average price for a gallon of regular unleaded gasoline fell below $2 per gallon, reaching $1.989 Friday, down 0.031 cents from Thursday, and down more than $2.12 from the July record of $4.114 per gallon, AAA said.