New mathematical record: what’s the point of calculating pi?

The famous number has many practical uses, mathematicians say, but is it really worth the time and effort to work out its trillions of digits?

Swiss researchers have spent 108 days calculating pi to a new record accuracy of 62.8tn digits.

Using a computer, their approximation beat the previous world record of 50tn decimal places, and was calculated 3.5 times as quickly. It's an impressive and time-consuming feat that prompts the question: why?