Purchasing Power Parity One of the more famous examples of a violation of absolute purchasing power parity is the Big Mac Index calculated by The Economist . This index calculates the dollar price of a McDonald's Big Mac in different countries. You can find the Big Mac Index by going to www.economist.com . Using the most recent index, which country has the most expensive Big Macs? Which country has the cheapest Big Macs? Why is the price of a Big Mac not the same in every country?