-84.05% is the change from 809 to 129
Calculation steps:
[( 129 - 809 ) ÷ 809] x 100 = -84.05%
Formula
Percentage change = [(129 - 809) / 809] x 100
Subtract the new number by the original number
129 - 809 = -680
-680 ÷ 809 = -0.8405438813349815
-0.8405438813349815 x 100 = -84.05%