US growth will be driven by the recovery of investment, which fell precipitously during the crisis. But, as investment now rises relative to saving, there is a danger that the US current-account deficit, which fell from 6% of GDP in 2006 to barely 2.5% of GDP last year, will widen again.
此外，如果要避免全球收支不平衡突然崩盘，双边汇率的调整只能是渐进的。在经历了危机中的暴跌之后已经，美国的投资水平有所恢复，这将驱动美国经济增长。但是目前也出现了投资增长快于储蓄增长的势头，美国经常账户赤字——从2006年占GDP的6%下降到去年的2.5%——有再次扩大的危险。