-20.72% is the change from 502 to 398
Calculation steps:
[( 398 - 502 ) ÷ 502] x 100 = -20.72%
Formula
Percentage change = [(398 - 502) / 502] x 100
Subtract the new number by the original number
398 - 502 = -104
-104 ÷ 502 = -0.20717131474103587
-0.20717131474103587 x 100 = -20.72%