MARATHON PETROLEUM REDUCES CRUDE POSTINGS Marathon Petroleum Co said it reduced the contract price it will pay for all grades of crude oil one dlr a barrel, effective today. The decrease brings Marathon's posted price for both West Texas Intermediate and West Texas Sour to 16.50 dlrs a bbl. The South Louisiana Sweet grade of crude was reduced to 16.85 dlrs a bbl. The company last changed its crude postings on Jan 12.