-39.14% is the change from 815 to 496
Calculation steps:
[( 496 - 815 ) ÷ 815] x 100 = -39.14%
Formula
Percentage change = [(496 - 815) / 815] x 100
Subtract the new number by the original number
496 - 815 = -319
-319 ÷ 815 = -0.3914110429447853
-0.3914110429447853 x 100 = -39.14%