据研究者芝加哥大学教授吴静和夏凡估计，美联储的无限期资产购买计划（所谓的量化宽松政策或QE）导致美国实际政策利率为-1.6 % 。
The researchers Cynthia Wu and Fan Dora Xia estimate that the US Federal Reserve’s open-ended asset purchases (so-called quantitative easing, or QE) have led to an effective US policy rate of -1.6%.