About 3.4 billion people live in rural areas under national definitions. According to the UN, that number should rise slightly and then fall to around 3.1 billion by 2050. Nearly 90% of rural dwellers live in Africa and Asia. The countryside is not just shrinking as a share of humanity: its population will soon start falling in absolute terms.
That's the estimate from a WHO-led study published in The Lancet in 2024, covering the half-century since the Expanded Programme on Immunization was launched in 1974. It works out to about six lives saved every minute, mostly infants. The measles vaccine alone accounts for around 60% of those lives.
According to the World Gold Council, about 216,000 tonnes of gold have been mined in all of human history. Because gold is so dense (19.3 tonnes per cubic metre), it would fit in a cube about 22 metres on each side, roughly the height of a seven-storey building. Strikingly, about two-thirds of it has been mined since 1950.