Americans may spend $52 billion more to fill their cars this year as OPEC output cuts boost oil prices and state tax hikes take a bigger bite, according to GasBuddy Organization Inc. The national yearly average will rise to $2.49 a gallon from $2.13 in 2016, analysts at GasBuddy, which tracks retail prices and availability,said in a 2017 outlook. The jump more than reverses the $39 billion decline last year.