The Big Mac became the subject of The Economist’s annual Big Mac Index, created in 1986.
The index uses the price of a Big Mac in different countries as an informal way to compare currency values and purchasing power. Its logic is based on purchasing-power parity: in theory, the same standardized product should cost a similar amount after exchange rates are taken into account, although real-world prices are affected by wages, rents, taxes, and local supply chains.
The Big Mac was especially suitable because McDonald’s sells a broadly standardized branded product in many countries. The index therefore turned a familiar piece of McDonald’s branding into a memorable economic reference point.
The Big Mac Index is not an official McDonald’s financial measure, and it is not a precise replacement for professional currency analysis. It is a lighthearted but widely cited illustration of international price differences. The burger itself was introduced regionally in 1967 and nationally in 1968.