Since the late January peak, oil prices have on average dropped 22 cents per gallon. : Average statewide prices for home heating oil have fallen 22 cents from their late-January peak, to $2.73 a gallon, Maine’s energy office found in its weekly survey on Tuesday, while average propane prices remain steady at $2.82. The changes reflect warmer weather following January’s extreme cold spell and a decline in global crude oil prices, the office said. Propane prices, in contrast, have been kept up by exports tied to a jump in domestic oil and gas production.