This animation shows big changes in the world's most populous cities over the next 80+ years. Africa alone will hold 13 cities bigger than NYC by...
The world's largest 123 cities generate an astonishing $36 trillion in GDP per year. This infographic breaks these global cities down into seven typologies.
That's right - nearly 4 billion people live inside the circle on this world map, including 22 of the world's 37 megacities.
