经济学家杂志用麦当劳巨无霸衡量的各国购买力平价汇率.doc

经济学家杂志用麦当劳巨无霸衡量的各国购买力平价汇率 The Big Mac Index Food for thought May 27th 2004 From The Economist print edition The world economy looks very different once countries output is adjusted for differences in prices !--back-- HOW fast is the world economy growing? How important is China as an engine of growth? How much richer is the average person in America than in China? The answers to these huge questions depend crucially on how you convert the value of output in different countries into a common currency. Converting national GDPs into dollars at market exchange rates is misleading. Prices tend to be lower in poor economies, so a dollar of spending in China, say, is worth a lot more than a dollar in America. A better method is to use purchasing-power parities (PPP), which take account of price differences. The theory of purchasing-power parity says that in the long run exchange rates should move towards rates that would equalise the prices of an identical basket of goods and services in any two countries. This is the thinking behind The Economists Big Mac index. Invented in 1986 as a light-hearted guide to whether currencies are at their “correct” level, our “basket” is a McDonalds Big Mac, which is produced locally in almost 120 countries. The Big Mac PPP is the exchange rate that would leave a burger in any country costing the same as in America. The first column of our table converts the local price of a Big Mac into dollars at current exchange rates. The average price of a Big Mac in four American cities is $2.90 (including tax). The cheapest shown in the table is in the Philippines ($1.23), the most expensive in Switzerland ($4.90). In other words, the Philippine peso is the worlds most undervalued currency, the Swiss franc its most overvalued. The second column calculates Big Mac PPPs by dividing the local currency price by the American price. For instance, in Japan a Big Mac costs ￥262. Dividing this by the American price of $2.90 produces a dollar