According to the UN, sub-Saharan African countries are expected to account for more than half of the increase in world population between now and 2050. The reasons: fertility is still relatively high, above 4 children per woman, and the population is very young, with a median age under 20. Fertility is falling there too, just more slowly than elsewhere, and projections are revised with each edition.
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.