-89.75% is the change from 966 to 99
Calculation steps:
[( 99 - 966 ) ÷ 966] x 100 = -89.75%
Formula
Percentage change = [(99 - 966) / 966] x 100
Subtract the new number by the original number
99 - 966 = -867
-867 ÷ 966 = -0.8975155279503105
-0.8975155279503105 x 100 = -89.75%