-90.44% is the change from 847 to 81
Calculation steps:
[( 81 - 847 ) ÷ 847] x 100 = -90.44%
Formula
Percentage change = [(81 - 847) / 847] x 100
Subtract the new number by the original number
81 - 847 = -766
-766 ÷ 847 = -0.9043683589138135
-0.9043683589138135 x 100 = -90.44%