事实上，大量研究表明，对大多数主要货币来说，对下周的汇率、下个月的汇率、或甚至明年的汇率最准确的预测，就是保持今天的汇率不变。
Indeed, a huge body of research shows that for most major currencies, the best forecast of next week’s exchange rate, next month’s exchange rate, or even next year’s exchange rate is simply today’s exchange rate.