-50.78% is the change from 831 to 409
Calculation steps:
[( 409 - 831 ) ÷ 831] x 100 = -50.78%
Formula
Percentage change = [(409 - 831) / 831] x 100
Subtract the new number by the original number
409 - 831 = -422
-422 ÷ 831 = -0.5078219013237064
-0.5078219013237064 x 100 = -50.78%