Here’s an interesting “center map” that shows the mean center of US population from 1790 to 2000. (Click on the image to view a larger version.)
The mean center of population is defined as the point at which an imaginary, flat, weightless, and rigid map of the United States would balance perfectly if weights of identical value were placed on it so that each weight represented the location of one person on the date of the census.
While the westward journey can be simply explained by the expansion of US population, the southward journey coincides with the invention of the modern electrical air-conditioners in the early 1900′s.
I wonder what the mean center of population of India is… somewhere in Madhya Pradesh, may be? Although Indians have been moving around more than ever before, the center of population has probably remained stable because the movement (which surely is directed towards the urbanized areas) may not be in any specific geographical direction.
[Hat Tip: Strange Maps]
[Picture courtesy: Wikipedia]