50% is the change from 136 to 204
Calculation steps:
[( 204 - 136 ) ÷ 136] x 100 = 50%
Formula
Percentage change = [(204 - 136) / 136] x 100
Subtract the new number by the original number
204 - 136 = 68
68 ÷ 136 = 0.5
0.5 x 100 = 50%
Example