Visit the link to interactively play with the data: https://public.tableau.com/profile/brad.ballard#!/vizhome/Top50CitiesbyGDPComparision/Dashboard
We often see lists of GDP by country, but rarely by city. This is puzzling because most countries are empty space and GDP output is concentrated in a few small areas. For example, about 50% of US GDP is generated on only 2% of its area – namely: cities. This is also the case around the world.
To put the importance of these 50 cities into perspective. The top 25 cities in the world generate 15.5 trillion dollars in GDP or 20.1% of total world GDP (2014 numbers). They do this with only 4.7% of world population and have a GDP per capita of 44 thousand dollars (4 times world average). The top 50 cities in the world generate 22.6 trillion dollars in GDP or 29.4% of total world GDP (2014 numbers). They do this with only 8.2% of world population and have a GDP per capita of 37 thousand dollars (3.5 times world average).
The GDP centers are clustered in geographic regions in North America, Western Europe, and Eastern Asia. Only a few cities are represented from the southern hemisphere and none from Africa or the Middle East. Asian cities tend to be larger in population, number of skyscrapers, and lower in GDP per capita. North American and Europen cities tend to have small-to-medium populations, low density, and a high GDP per capita.