Oil dips but set for biggest yearly gain since 2009

Oil traded slightly lower on Friday, but was still on track for its biggest annual gain since 2009, after OPEC and other major producers agreed to cut output to reduce a global supply overhang that has depressed prices for two years. U.S. benchmark West Texas Intermediate (WTI) crude futures were down 18 cents. Oil prices have slumped since the summer of 2014 from above $100 a barrel.