In the past year, oil has blown by $50 a barrel and peaked briefly at $70 altitudes, sending prices at the gas pump temporarily into the psychologically jarring territory north of $3 a gallon.

• 过去的一年，油价已突破每桶五十美元，并在七十美元大关作短暂停留，加油站的价格一度令北部地区心惊肉跳，达到每加仑三美元。