It's National Numeracy Day! As part of the Millennium Mathematics Project we're delighted to be helping the Government Office for Science (GO-Science) with this sporting maths challenge! Gather together your family, friends and colleagues and get puzzling.

The graphs below show all the Olympic records set in four track and field Athletics events.

Can you work out which events are shown in the graphs?

Thinking about these questions might help you get started:

Why do some of the graphs show the records increasing (going up) and on others the records decrease (go down)?

The horizontal (bottom) axis of each graph shows the dates of the Olympic Games. The units of measurement on the vertical axis are deliberately not labelled - can you work out what they could be?

What can you tell from the dates when the records start and stop?

Can you see any other interesting information from the graphs? Can you do some research to find out more?

You can see the answers here!

This challenge is based on an updated activity first developed by our NRICH colleagues for the Millennium Mathematics Project's 'Maths and Sport: Countdown to the Games' initiative for the London 2012 Olympic and Paralympic Games, which was a partner project in the London 2012 Get Set+ education programme, and was awarded the London 2012 Inspire Mark. Thank you to Alan Parr for originally suggesting the idea.