28.1% is the change from 121 to 155
Calculation steps:
[( 155 - 121 ) ÷ 121] x 100 = 28.1%
Formula
Percentage change = [(155 - 121) / 121] x 100
Subtract the new number by the original number
155 - 121 = 34
34 ÷ 121 = 0.2809917355371901
0.2809917355371901 x 100 = 28.1%