The population sizes of the cities in the world follow the same distribution in the past 30 years

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This week has been busy. Since yesterday I have been working on the paper discussing the population size data of all the cities in the world. There are some very interesting findings and I can write several posts about it.

One interesting finding is that contrary to some prevalent imagination that there are more and more large cities and the small cities are diminishing, our findings based on the population data of all the cities in the world since the year 1990 indicate such statement is wrong. More large cities do not necessarily imply fewer small cities. Thus, when there are more large cities, there are also more small cities proportionally. And since the total number of cities with size above 100 thousand is increasing, the share of small or large cities in the world remains the same.


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