ALONG with bank runs and market crashes, oil shocks have rare power to set monsters loose. Starting with the Arab oil embargo of 1973, people have learnt that sudden surges in the price of oil cause economic havoc. Conversely, when the price slumps because of a glut, as in 1986, it has done the world a power of good. The rule of thumb is that a 10% fall in oil prices boosts growth by 0.1-0.5 percentage points.

除了银行挤兑和(金融)市场崩盘，如猛兽一般破笼而出的还有油价大跌。从1973年阿拉伯石油禁运开始，人们就懂得油价飙升将导致经济浩劫。相反，正如1986年那样，油价若是因为供过于求而跌价，那么这对全世界来说是极好的。经验法则是这样的：原油掉价10%，会带来0.1%到0.5%的经济增长点。

In the past 18 months the price has fallen by 75%, from $110 a barrel to below $27. Yet this time the benefits are less certain. Although consumers have gained, producers are suffering grievously. The effects are spilling into financial markets, and could yet depress consumer confidence. Perhaps the benefits of such ultra-cheap oil still outweigh the costs, but markets have fallen so far so fast that even this is no longer clear.

过去的18个月里，原油油价降了75%，从每桶110美元降到每桶27美元。然而这一次的受益却不太确定。尽管消费者们受益颇多，但是生产商却损失惨重。损失波及金融市场，可能已经打击了消费者信心，也许如此极度廉价的原油所带来的益处依旧大于其带来的损失，但是金融市场崩溃地如此厉害如此迅速，这一点原因还尚未明朗。