This is exactly what I want, and what I would do if the data was structured the way it's set up for you. The problem I have is that the way I'm retrieving the data is from 2 different feeds which I then combine. That means I don't have the EUR and GBP price in the same row. The example I gave was how the data looks like after I have made a sheet and combined the data.
The data I'm working with is structured in the following way
uid(The way I can combine the eur and gbp feeds), currency, start_date, end_date, price and discount.
So in the example I gave in the original post I have all ready done this calculation
And then calculated the % difference between the two prices.
I'm having troubles with this as the % calculation is generated from 2 rows and not 1, and is searching for ways to solve that.