Several Orthodox churches, including those of Russia, Serbia, Georgia and Jerusalem, still use the Julian calendar to set their feast days. That calendar, introduced under Julius Caesar, has drifted 13 days behind the Gregorian one, so their 25 December falls on our 7 January. The gap will keep widening: next century, this Christmas will fall on 8 January. Other Orthodox churches, such as those of Greece and Romania, celebrate Christmas on 25 December.
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.