150% is the change from 102 to 255
Calculation steps:
[( 255 - 102 ) ÷ 102] x 100 = 150%
Formula
Percentage change = [(255 - 102) / 102] x 100
Subtract the new number by the original number
255 - 102 = 153
153 ÷ 102 = 1.5
1.5 x 100 = 150%
Example