-87.42% is the change from 636 to 80
Calculation steps:
[( 80 - 636 ) ÷ 636] x 100 = -87.42%
Formula
Percentage change = [(80 - 636) / 636] x 100
Subtract the new number by the original number
80 - 636 = -556
-556 ÷ 636 = -0.8742138364779874
-0.8742138364779874 x 100 = -87.42%