Economic indicators are essential for understanding a country's economic outlook, offering metrics for accurately assessing the economic landscape. They can be official, calculated by government sources, or informal.
One of the best-known informal indicators is the Big Mac Index, created in the 1980s by The Economist magazine. It offers a unique view of currency purchasing power by comparing the price of a Big Mac in different countries.
This economic indicator uses McDonald's hamburger prices in different countries to estimate disparities in global purchasing power and is based on the theory of purchasing power parity (PPP). PPP suggests that, in the long term, exchange rates between two currencies should adjust so that an identical good costs the same in both currencies.
This is an interesting way to determine purchasing power in different countries, since the Big Mac is sold in practically every part of the world and, because its production is nearly the same everywhere, should have similar prices for the final consumer. Thus, calculating the difference in the final price of a Big Mac can provide an informal perspective on the difference in purchasing power between two or more countries.
For comparison, the US dollar is the currency used for comparative calculations. For example, if the price of a Big Mac in one country is lower when converted to dollars at the current exchange rate, this suggests that the local currency is undervalued against the dollar. If the price is higher, it indicates an overvalued currency. This simple approach provides a direct and tangible understanding of purchasing-power disparities and exchange-market nuances.
How does it work in practice?
Recently, we have observed considerable changes in exchange rates between different countries' currencies. One notable fluctuation occurred between the Brazilian real (BRL) and the Argentine peso (ARS). How can the Big Mac Index be used to understand this situation?
In a hypothetical example, if a Big Mac in Argentina cost 1,650 Argentine pesos, equivalent to US$5.99, while the same meal cost US$5.59 in the United States, this difference would suggest that the Argentine peso was overvalued against the dollar. Conversely, if the Brazilian real were undervalued and it took fewer dollars to buy the same meal, that would indicate an appreciation of the real against the Argentine peso in this exchange relationship.
Although intuitive, the index is imprecise and ignores important variables
Although the Big Mac Index is an interesting tool for comparing purchasing power between countries, it has significant limitations. The price of a Big Mac can be influenced by local factors such as taxes, labor costs, and trade tariffs, which distort the index's accuracy. In addition, the index does not consider other important economic variables, such as income levels, inflation, and fiscal and monetary policies, which affect purchasing power.
Therefore, although intuitive and easy to calculate, the Big Mac Index is not the best metric for assessing purchasing power parity between countries, because it ignores many economic and local variables. However, it can be an interesting basis for beginners studying and learning more about economics, encouraging people to deepen their economic knowledge.
