509.52% is the change from 42 to 256
Calculation steps:
[( 256 - 42 ) ÷ 42] x 100 = 509.52%
Formula
Percentage change = [(256 - 42) / 42] x 100
Subtract the new number by the original number
256 - 42 = 214
214 ÷ 42 = 5.095238095238095
5.095238095238095 x 100 = 509.52%