-89.25% is the change from 921 to 99
Calculation steps:
[( 99 - 921 ) ÷ 921] x 100 = -89.25%
Formula
Percentage change = [(99 - 921) / 921] x 100
Subtract the new number by the original number
99 - 921 = -822
-822 ÷ 921 = -0.8925081433224755
-0.8925081433224755 x 100 = -89.25%