-80.08% is the change from 502 to 100
Calculation steps:
[( 100 - 502 ) ÷ 502] x 100 = -80.08%
Formula
Percentage change = [(100 - 502) / 502] x 100
Subtract the new number by the original number
100 - 502 = -402
-402 ÷ 502 = -0.8007968127490039
-0.8007968127490039 x 100 = -80.08%