The world at seven billion
25 October 2011 Last updated at 21:16 BST
The UN is set to announce that the population of the planet has now reached seven billion people.
But will this number continue to rise in future years - and if so, what could this mean?
The BBC's Fergus Walsh crunches the numbers to find out.
Production: Anna-Marie Lever, John Galliver, Emily Jones. Design: David Gordon, George Spencer, Amanda Constantino.
Camera: Tony Dolce, Graham Hodson and Julius Peacock.