-91.12% is the change from 912 to 81
Calculation steps:
[( 81 - 912 ) ÷ 912] x 100 = -91.12%
Formula
Percentage change = [(81 - 912) / 912] x 100
Subtract the new number by the original number
81 - 912 = -831
-831 ÷ 912 = -0.9111842105263158
-0.9111842105263158 x 100 = -91.12%