-8.91% is the change from 909 to 828
Calculation steps:
[( 828 - 909 ) ÷ 909] x 100 = -8.91%
Formula
Percentage change = [(828 - 909) / 909] x 100
Subtract the new number by the original number
828 - 909 = -81
-81 ÷ 909 = -0.0891089108910891
-0.0891089108910891 x 100 = -8.91%