McDonald's is a restaurant, but it functions much like a factory. Labor is supported by a deep well of technological innovation, such as vacuum packing, exceptional preservatives, deep freezing, vibrant artificial flavors, and high-speed microwaves. Workers assemble specific parts at great speed to deliver dependable and replicable products. "[McDonald's doesn't] put something on the menu until it can be produced at the speed of McDonald's," CEO James Skinner said in 2010, sounding not unlike Henry Ford from a century earlier.



In addition to being a technological marvel, the Big Mac moonlights as an economic tool. Every year the Economist calculates a Big Mac Index for the purpose of (being cheeky and) testing what currencies are overvalued compared to the U.S. The results are often illuminating. This year identified Switzerland and Brazil as particularly overvalued. The flight from euros is lifting the franc and the real's appreciation has blunted Brazil's export growth. So, the Big Mac isn't just some dumb lump of something resembling meat. It's an international barometer of economic activity.

And now, in a research paper released last week, Princeton's Orley C. Ashenfelter has done something truly fascinating with the Big Mac. He used the world's most famous sandwich to help us answer one of the trickiest questions in all of economics:



How do poor nations get rich?

BIG MACONOMICS

The world's nations are diverse in ways that defy easy comparisons. But at least 118 of them share something similar. They have a McDonald's.



In every McDonald's around the world, workers perform similar tasks with similar, shipped ingredients stored in similar freezers and prepared according to similar international protocol. This matters to economists, because McDonald's offers an international apples-to-apples comparison of wages and prices.



Ashenfelter comes up with a clever way to measure wage growth, or purchasing power parity, across the globe. By recording wages and Big Mac prices over time, he computes how many Big Macs one can buy on an hour's salary in the U.S. vs. Western Europe vs. the developing world. Tracking Big-Macs-per-hours-worked, he says, should tell us who's really rich, who's getting rich, and who's not.



And, as it turns out, Big Macs and McWages explain three of the most important ideas in international economics: (1) The Rise of the West; (2) The Rise of the Rest; and (3) The Great Recession.



The Rise of the West. Countries get rich because they become particularly skilled in certain industries that they can sell in exchange for money. So why are McDonald's workers in the U.S. or Western Europe earning up to 10-times more than in India, China, or Latin America? It's not that Chinese and Chileans are less skilled at heating burgers. Rather it has everything to do with the economy outside of McDonald's kitchens.

