经济学人下载:日益强大的汉堡经济学

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Beefed-up burgernomics
日益强大的汉堡经济学

Jul 30th 2011 | from the Economist print edition

A gourmet version of the Big Mac index suggests that the yuan is not that undervalued
以美食家的角度来看巨无霸经济指数，人民币并未被低估

THE Big Mac index celebrates its 25th birthday this year. Invented by The Economist in 1986 as a lighthearted guide to whether currencies are at their “correct” level, it was never intended as a precise gauge of currency misalignment, merely a tool to make exchange-rate theory more digestible. Yet the Big Mac index has become a global standard, included in several economic textbooks and the subject of at least 20 academic studies. American politicians have even cited the index in their demands for a big appreciation of the Chinese yuan. With so many people taking the hamburger standard so seriously, it may be time to beef it up.

巨无霸指数已经诞生25年了。在1986年的一期经济学人杂志中第一次出现，当初仅仅是为了让人们更易理解汇率，随意的作为一个衡量货币是否在“正常”水平的指标，人们从没有指望它能作为一个估评货币的标准。然而如今巨无霸指标已经成为国际的一个标准，被数个经济读本引用还成为至少20个学术研究的课题。美国的政客们甚至借这一数字来要求中国人民币的增值。鉴于人们如此看重汉堡指数，可能是时候去讨论一下它的意义了。

Burgernomics is based on the theory of purchasing-power parity (PPP), the notion that in the long run exchange rates should move towards the rate that would equalise the prices of an identical basket of goods and services (in this case, a burger) in any two countries. The average price of a Big Mac in America is $4.07; in China it is only $2.27 at market exchange rates, 44% cheaper. In other words, the raw Big Mac index suggests that the yuan is undervalued by 44% against the dollar. In contrast, the currencies of Switzerland and Norway appear to be overvalued by around 100%. The euro (based on a weighted average of prices in member countries) is overvalued by 21% against the dollar; sterling is slightly undervalued; the Japanese yen seems to be spot-on. For the first time, we have included India in our survey. McDonald’s does not sell Big Macs there, so we have taken the price of a Maharaja Mac, made with chicken instead of beef. Meat accounts for less than 10% of a burger’s total cost, so this is unlikely to distort results hugely. It indicates that the rupee is 53% undervalued.

以购买力等价理论（PPP）为基础，汉堡经济旨在表示任意两个国家，长期以来保持的汇率应该趋于使人们消费在同样的商品或服务（这里指汉堡）的金钱持平。在美国巨无霸的价格平均为每个$4.07，而在中国经市场汇率计算仅为$2.27，便宜了44%。换句话说，原始的巨无霸指数显示人民币较美元被低估了44%。另一方面瑞士和挪威的货币则约被高估了100%。欧元（根据成员国的价格加权平均值）较美元高估了21%；英镑低估了一点点，日元则和美元持平。这是我们第一次将印度囊括在调查的国家中，因为麦当劳并不在印度销售巨无霸，于是我们选取印度版巨无霸来研究，汉堡里面夹的是鸡肉而不是牛肉。但肉的价格占整个汉堡价格的比例小于10%，所以这也不会使结果产生太大偏差。结果显示，卢比的汇率被低估了53%。