-90.21% is the change from 878 to 86
Calculation steps:
[( 86 - 878 ) ÷ 878] x 100 = -90.21%
Formula
Percentage change = [(86 - 878) / 878] x 100
Subtract the new number by the original number
86 - 878 = -792
-792 ÷ 878 = -0.9020501138952164
-0.9020501138952164 x 100 = -90.21%