Gas prices are down slightly across Arizona this week. Triple-A Arizona says prices fell about a half-cent to $2.34 a gallon. In Flagstaff, gas was down almost two cents a gallon from last week to $2.40 a gallon this week. Some stations are selling gas for $2.33 and lower. In Prescott, gas was unchanged, sitting at $2.35 a gallon. Some stations are selling gas for $2.21 and lower. Officials say even though demand is up, oil prices are lower which leads to very little change at the pump.