Gasoline costs more these days, but price spikes have a long history and happen for a host of reasons

Americans are acutely sensitive to gasoline prices, especially when they’re on the rise. One reason, of course, is that we buy a lot of gas: an estimated 570 gallons this year for the average driver, which at current national average prices would cost close to $2,000. Also, gas prices are posted all over town on large signs – unlike, say, milk prices – and people typically buy gas on its own rather than as part of a larger shopping trip, making price changes more noticeable. And gas prices can and do swing sharply and...