Gasoline prices in Iowa have dipped a bit in the past month according to David Downing, a state fuel market analyst.Downing says the latest state survey shows the average price for a gallon of unleaded gas was a dollar-32; and a dollar-30 for ethanol. That’s a four-cent drop from mid-April to mid-May. Downing says the major reason for the price decline was the decline in demand.Downing says the weather recently hasn’t been conducive to travel, and that’s helped push down the demand for gasoline. He says inventories have built behind strong refinery production and imports of gas.Downing says last year at this time, gasoline prices were 43-cents-per-gallon higher.