-48.7% is the change from 501 to 257
Calculation steps:
[( 257 - 501 ) ÷ 501] x 100 = -48.7%
Formula
Percentage change = [(257 - 501) / 501] x 100
Subtract the new number by the original number
257 - 501 = -244
-244 ÷ 501 = -0.4870259481037924
-0.4870259481037924 x 100 = -48.7%