-88.79% is the change from 812 to 91
Calculation steps:
[( 91 - 812 ) ÷ 812] x 100 = -88.79%
Formula
Percentage change = [(91 - 812) / 812] x 100
Subtract the new number by the original number
91 - 812 = -721
-721 ÷ 812 = -0.8879310344827587
-0.8879310344827587 x 100 = -88.79%