-50.2% is the change from 504 to 251
Calculation steps:
[( 251 - 504 ) ÷ 504] x 100 = -50.2%
Formula
Percentage change = [(251 - 504) / 504] x 100
Subtract the new number by the original number
251 - 504 = -253
-253 ÷ 504 = -0.501984126984127
-0.501984126984127 x 100 = -50.2%