By Ray DiLorenzo It confuses many people. Myself included. I will attempt to simplify these complex concepts so that even I can grasp them. Oil is a globally priced commodity. Pump prices in the U.S. follow world supply and demand without concern for how much we produce. People often ask why the pump price goes up so quickly even when the gas at the station was bought at a lower price. The price at the pump does not reflect the price paid but the replacement cost. The same principle applies in...