Fergus Walsh
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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.