-98.15% is the change from 811 to 15
Calculation steps:
[( 15 - 811 ) ÷ 811] x 100 = -98.15%
Formula
Percentage change = [(15 - 811) / 811] x 100
Subtract the new number by the original number
15 - 811 = -796
-796 ÷ 811 = -0.9815043156596794
-0.9815043156596794 x 100 = -98.15%