-84.8% is the change from 809 to 123
Calculation steps:
[( 123 - 809 ) ÷ 809] x 100 = -84.8%
Formula
Percentage change = [(123 - 809) / 809] x 100
Subtract the new number by the original number
123 - 809 = -686
-686 ÷ 809 = -0.8479604449938195
-0.8479604449938195 x 100 = -84.8%