Due to heavy urban migration, city slums are continuing to spread. They become the clearest piece of evidence that large cities are not planned to ensure that everyone has access to water, housing and basic sanitation.
Today, an estimated 863 million live in slums around the world. The number increased from 650 million in 1990 to 760 million in 2000.
In Africa south of the Sahara, 61.7% live in slums.
Source: World Migration Report 2015