OPEC crude production dropped to a two-year low in November, led by declines in Saudi Arabian and Nigerian output, a Bloomberg survey showed. Output by the 12-member Organization of Petroleum Exporting Countries decreased 245,000 barrels to an average 30.007 million barrels a day this month from 30.252 million in October, the survey of oil companies , producers and analysts showed. The October total was revised lower by 369,000 barrels a day because of changes to the Saudi and Libyan estimates. Saudi Arabian crude output declined 150,000 barrels a day to 9.65 million. The desert kingdom pumped 10 million barrels a day in September, the most in monthly data going back to 1989. The October estimate was reduced by 200,000 barrels a day. Nigeria’s production dropped 100,000 barrels a day to 1.89 million in November, the lowest level since May. Production is often disrupted by unrest in the Niger River […]