How many adverts does the average person see in a day? If you search for this question online, the surprising answer is that we might see thousands – up to 10,000.

However, the idea that we see thousands of adverts is a strange and confusing one, without any good research behind it. We investigate the long history of these odd numbers, with the help of Sam Anderson from The Drum and J Walker Smith from Kantar.

Presenter: Tim Harford
Series producer: Tom Colls
Production co-ordinator: Brenda Brown
Sound Mix: James Beard
Editor: Richard Vadon