-39% is the change from 823 to 502
Calculation steps:
[( 502 - 823 ) ÷ 823] x 100 = -39%
Formula
Percentage change = [(502 - 823) / 823] x 100
Subtract the new number by the original number
502 - 823 = -321
-321 ÷ 823 = -0.39003645200486026
-0.39003645200486026 x 100 = -39%