-89.12% is the change from 910 to 99
Calculation steps:
[( 99 - 910 ) ÷ 910] x 100 = -89.12%
Formula
Percentage change = [(99 - 910) / 910] x 100
Subtract the new number by the original number
99 - 910 = -811
-811 ÷ 910 = -0.8912087912087913
-0.8912087912087913 x 100 = -89.12%