The amount of water on earth hasn’t changed in millions of years. The number of people who use it has. Here are a few surprising numbers:

344 million cubic miles – this figure is the total amount of water on earth. That number is quite hard to relate to, but the really important fact is that less than 1% can be used as drinking water.

884 million – the number of people in the world who don’t have access to safe water

4,000 – every day this many children die of diarrhoea caused by dirty water and a lack of sanitation

5 – Americans use five times as much water as Europeans, and 20 times as much as the poorest people on the planet

2,700 – years ago was when the first flushing toilets were used in Pakistan and India