While average life expectancy for many cities far outstrips the non-urban regions of their country, there are others such as Johannesburg where it comes in way below. This interactive map uses a mixture of data from LSE Cities and the World Health Organisation to compare the national average with that of specific cities.
If the dot is red then the city’s life expectancy is below the national average; if green then it is above. The shading tells you by how much it is over or under either way
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