In 2005, US Federal Reserve Chair Alan Greenspan pointed to the phenomenon as an explanation for his famous “conundrum”: interest rates on Treasury bonds were lower than market conditions appeared to warrant. His successor, Ben Bernanke, similarly pointed to purchases of US debt by foreign central banks and governments as a reason why American interest rates were so low.
这些买入美国国债的行为所造成的效果吸引了大量关注。2005年，美联储主席艾伦·格林斯潘（Alan Greenspan）用这一现象解释他著名的“谜”论：美国国债利率比市场条件所隐含的水平还要低。类似地，他的继任者本·伯南克（Ben Bernanke）也将外国央行购买国债描述为美国利率如此低的一个原因。