Where people are moving

And the growth of supercities - it's interesting that the only country in a developed country is London at #10 (Quartz via Chris Blattman).

It's measured by the largest migrations where at least 20% of a city's population is from elsewhere - which raises interesting questions as to whether or not the growth is sustainable. Migrants will often bring differing values, ideas and depend on how migrants integrate into their new destinations.