-49.21% is the change from 504 to 256
Calculation steps:
[( 256 - 504 ) ÷ 504] x 100 = -49.21%
Formula
Percentage change = [(256 - 504) / 504] x 100
Subtract the new number by the original number
256 - 504 = -248
-248 ÷ 504 = -0.49206349206349204
-0.49206349206349204 x 100 = -49.21%