Only a handful of currencies are close to their Big Mac PPP.

ECONOMIST: The Big Mac Index

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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The Economist's Big Mac index offers a crude estimate of how far exchange rates are from PPP.

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