153.33% is the change from 255 to 646
Calculation steps:
[( 646 - 255 ) ÷ 255] x 100 = 153.33%
Formula
Percentage change = [(646 - 255) / 255] x 100
Subtract the new number by the original number
646 - 255 = 391
391 ÷ 255 = 1.5333333333333334
1.5333333333333334 x 100 = 153.33%