by Daniel Velkov, for comments go to Hacker News

The story starts with an insightful graphic which was published in The Economist. The original work was done by the McKinsey Global Institute which itself is based on data collected by the University of Groningen (link to the raw spreadsheet).

The graphic plots the movement of the world's geographic center of economic activity for the years between 1 and 2025. There was one thing which bothered me, and I hope it bothers you too, the points from the 20th century are all positioned in or above Scandinavia which seems unlikely to be the center of anything in the world. You can find the reason for that in the caption on the McKinsey webpage. Their report looks at the Earth as a sphere and finds the economic center of gravity which falls somewhere inside the sphere. To plot it on the map, they take a radius through the center of gravity and intersect it with the surface. To see why this is a problem, consider the extreme case of only USA and China existing and their economies being equally sized. In this setup the economic center will be close to the North Pole because the two countries happen to be on almost the exact opposite sides of the Earth and roughly at the same latitude.

I had an idea how to visualize the same data in a better and more intuitive way. Instead of the original method, I did all the calculations in 2D with respect to the usual map coordinates. This has the nice property that in the USA/China case from above, the center will end up somewhere near Spain which is the midway point between USA and China on most maps. The result of this approach is:

You can see that it shows the same directional trends as the first chart. In the year 1 AD the world's economic center is close to China and India. Looking back at the spreadsheet for that year, you can see that the total economic output of Asia is 5 times larger than Europe's. There is a slight move to the east, in the years 1-1600, which is due to the decline of the Roman Empire and Europe in general during that time. As time progresses, Europe's economy rises and the center starts shifting west. With the help of the US, this movement continues until 1950 when the trend reverses. The return of the Asian economies starts pushing the point east and in 2000 the position is at the same level on the east-west axis as it was in 1900.