时间和刊物：IMES Discussion Paper 2010
摘要：The center country of the International Monetary System enjoys an “exorbitant privilege” that significantly weakens its external constraint. In exchange for this “exorbitant privilege” we document that the US provides insurance to the rest of the world, especially in times of global stress.（即：美元是全球经济保险）
思考的特殊之处：在于提出了一个跨时期的解释。通常人们在解释为什么美国有exorbitant privilege时，想起的总是深层的运作机制（流动性、中介货币优势），但这篇文章的特殊之处，在于跨时期地想了问题——在正常时期美元系统是有溢价的，但在经济困难时期，美元系统有巨大损失——所以，美元系统就像一个保险系统。
insurance properties of international currency
正文：
定义：The existence of a lasting “exorbitant privilege” -a higher return on US external assets than on its external liabilities. (意义：allowing it to run larger trade and current account deficits without worsening its external position commensurately)
发现：the excess total return of US gross external assets over its gross external liabilities is worth about 2% per year between 1952 and 2009.
Exorbitant Duty：
原理：the valuation of US Treasury Bills and bonds did not collapse during the crisis, like those of all the other assets. Coupled with the appreciation of the dollar, the relative stability in the value of US bonds has led to a massive wealth transfer of the US towards the rest of the world.
传统观点（解释Exorbitant Privilege）：Traditional views rely on liquidity effects and the medium of exchange function of money
总结出的四个事实：
Model：
Consumption/Utility/Business Cycle
结论：
