-91.32% is the change from 991 to 86
Calculation steps:
[( 86 - 991 ) ÷ 991] x 100 = -91.32%
Formula
Percentage change = [(86 - 991) / 991] x 100
Subtract the new number by the original number
86 - 991 = -905
-905 ÷ 991 = -0.9132189707366297
-0.9132189707366297 x 100 = -91.32%