-89.37% is the change from 931 to 99
Calculation steps:
[( 99 - 931 ) ÷ 931] x 100 = -89.37%
Formula
Percentage change = [(99 - 931) / 931] x 100
Subtract the new number by the original number
99 - 931 = -832
-832 ÷ 931 = -0.8936627282491945
-0.8936627282491945 x 100 = -89.37%