购买力平价与人民币均衡汇率

Purchasing Power Parity and Equilibrium Exchange Rate of RMB

购买力平价是衡量均衡汇率的最为重要的方法之一,依此方法对人民币低估程度的估计也曾经是最为严重的。本文就如何适当运用购买力平价来度量均衡汇率的问题做了系统性的文献回顾和评论。结合近期的相关研究,我们指出了在一些有关于人民币均衡汇率的讨论中所存在的需要商榷乃至于错误的地方。本文认为:相对于基本均衡汇率等方法,扩展型的购买力平价方法更适合于度量人民币均衡汇率水平;世界银行2005年购买力平价数据显著降低了关于人民币低估程度的估计,根本性改变了人民币汇率问题争议的形势,而有关世界银行数据本身被低估的观点未必成立;最后,当前人民币汇率并不存在严重的低估。

Purchasing Power Parity （PPP） is one of the most widely used methods to measure the equilibrium exchange rate of a currency. Employing the method, some studies have arrived at the highest estimations on the level of RMB undervaluation. This paper provides a comprehensive review on the existing literature especially recent discussions, pointing out several misuses and mistakes that commonly appear in related studies. It is pro- posed in this paper that ： （ 1 ） compared to other approaches such as FEER, extended PPP method is more prop- er in measuring RMB＇s equilibrium exchange rate; （2） World Bank＇s revision on China＇s PPP in 2005 has sig- nificantly reduced estimation on RMB undervaluation level; and the view that new PPP for China was underestimated is not convincingly held; （3） The current RMB exchange rate is not seriously undervalued.