-34.19% is the change from 503 to 331
Calculation steps:
[( 331 - 503 ) ÷ 503] x 100 = -34.19%
Formula
Percentage change = [(331 - 503) / 503] x 100
Subtract the new number by the original number
331 - 503 = -172
-172 ÷ 503 = -0.341948310139165
-0.341948310139165 x 100 = -34.19%