-87.64% is the change from 809 to 100
Calculation steps:
[( 100 - 809 ) ÷ 809] x 100 = -87.64%
Formula
Percentage change = [(100 - 809) / 809] x 100
Subtract the new number by the original number
100 - 809 = -709
-709 ÷ 809 = -0.8763906056860321
-0.8763906056860321 x 100 = -87.64%