-98.15% is the change from 809 to 15
Calculation steps:
[( 15 - 809 ) ÷ 809] x 100 = -98.15%
Formula
Percentage change = [(15 - 809) / 809] x 100
Subtract the new number by the original number
15 - 809 = -794
-794 ÷ 809 = -0.9814585908529048
-0.9814585908529048 x 100 = -98.15%