Crude oil prices tumbled Wednesday, dropping under $93 per barrel as traders waited for a U.S. stockpile report due in the afternoon. Crude oil made a run toward $100 per barrel early in the week, but the rally slid away with West Texas Intermediate crude oil for October delivery giving up an additional $2.36 on the New York Mercantile Exchange to reach $92.93 per barrel. Natural gas added 6.1 cents early to $2.834 per million British thermal unit. Home heating oil lost 6.4 cents to $3.0631 per gallon. Reformulated blendstock gasoline shed 5.49 cents to $2.8441 per gallon. At the pump, the average price for a gallon of regular unleaded gasoline was $3.854 per gallon, down from Tuesday\'s $3.859, AAA reported.