The Big Mac index was introduced in The Economist in September 1986 by Pam Woodall as a semi-humorous illustration mcdonalds large big mac meal calories PPP and has been published by that paper annually since then. The theory underpinning the Big Mac index stems from the concept of PPP, which states that the exchange rate between two currencies should equalize the prices charged for an identical basket of goods. However, in reality, sourcing an identical basket of goods in every country provides a complex challenge.
The purpose of the Big Mac index is to calculate an implied exchange rate between two currencies. Typically, the base country used is the United States. In Switzerland, a Big Mac costs 6. The implied exchange rate is 1.
The implied exchange rate according to the Big Mac index is 1. The actual exchange rate is 0. The Swiss franc is overvalued by 20. The Economist sometimes produces variants on the theme. For example, in January 2004, it showed a Tall Latte index with the Big Mac replaced by a cup of Starbucks coffee.