The index is based on the idea of purchasing-power parity (PPP), which says currencies should trade at the rate that makes the price of goods the same in each country.

指数在购买力平价（PPP）这一概念基础上产生，购买力平价是指货币应以使商品价格在各个国家保持一致的汇率兑换。

youdao

The Big Mac Index is based on the theory of purchasing-power parity (PPP), which says that exchange rates should move to make the price of a basket of goods the same in each country.

巨无霸指数是建立在购买力平价理论的基础上。 购买力平价理论认为，汇率应该使得一揽子商品的价格在各个国家都相同。

youdao

THE Big Mac index is based on the theory of purchasing-power parity (PPP)—exchange rates should equalise the price of a basket of goods in different countries.

巨无霸指数基于购买力平价理论，该理论认为汇率应该使不同国家的一揽子商品的价格相等。

youdao

The Big Mac Index uses Purchasing Power Parity (PPP) in comparing the price of the ubiquitous Big Mac across countries relative to its price in the USA. PPP refers to the idea that exchange rates across two countries should be equal to the relative price of a basket of goods and services in both countries.

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