The Big Mac Index, the informal economic gauge created by The Economist to measure whether currencies are at their correct value, turned 40 this year and remains a relevant tool for tracking currency relationships between countries, according to MarketWatch.
The index, which uses the price of a McDonald's Big Mac as a baseline comparison across countries, was originally introduced as a lighthearted way to illustrate the concept of purchasing power parity. The idea is that a burger should cost roughly the same everywhere once exchange rates are accounted for. When it costs significantly less in one country, that country's currency may be undervalued relative to the dollar.
Burgers are broadly cheaper across Asia, where the price gap with the United States remains wide. That finding carries particular relevance today. The U.S. president has accused several countries in the region of currency manipulation, and the price of a Big Mac offers one informal data point in that ongoing debate.
The index has endured for four decades in part because it translates a complex economic concept into something concrete and easy to understand. Purchasing power parity can be difficult to explain using standard economic data. A hamburger price is not.
While economists do not use the Big Mac Index as a formal policy tool, it has proven durable as a way to illustrate broad currency misalignments. Its 40-year track record has given it a place in both academic discussions and mainstream financial coverage.
The index continues to be updated regularly, with the latest figures reflecting current exchange rates and local McDonald's pricing around the world.
