126.56% is the change from 256 to 580
Calculation steps:
[( 580 - 256 ) ÷ 256] x 100 = 126.56%
Formula
Percentage change = [(580 - 256) / 256] x 100
Subtract the new number by the original number
580 - 256 = 324
324 ÷ 256 = 1.265625
1.265625 x 100 = 126.56%