CNBC | Why oil prices went from four-year highs to a bear market in just six weeks CNBC As a result, oil prices have plunged more than $20 a barrel since the start of October, when Brent crude rose to nearly $87 a barrel and U.S. crude traded just shy of $77. Both benchmarks are now trading firmly in bear market territory, having fallen ... Oil rout runs to 12 days on supercharged selling Oil price resumes its decline Oil is extending its record losing streak to a 12th day |