If you have a discounted price and an original price, and you want to know the discount as a percentage, you can calculate the percentage discount using a formula that divides the discounted price by the original price and then subtracts the result from one.
= 1 - (discount_price / original_price)
How the formula works In the example?
Excel first divides the discounted price by the original price in to get value, which is then subtracted from 1: =1-(59.5/70) =1-0.85 =0.15
Note that the result is a decimal version of the percent, and must be formatted using the Percentage number format in Excel to display as a percentage.