152.34% is the change from 256 to 646
Calculation steps:
[( 646 - 256 ) ÷ 256] x 100 = 152.34%
Formula
Percentage change = [(646 - 256) / 256] x 100
Subtract the new number by the original number
646 - 256 = 390
390 ÷ 256 = 1.5234375
1.5234375 x 100 = 152.34%