-61.8% is the change from 809 to 309
Calculation steps:
[( 309 - 809 ) ÷ 809] x 100 = -61.8%
Formula
Percentage change = [(309 - 809) / 809] x 100
Subtract the new number by the original number
309 - 809 = -500
-500 ÷ 809 = -0.6180469715698393
-0.6180469715698393 x 100 = -61.8%