40.5% is the change from 121 to 170
Calculation steps:
[( 170 - 121 ) ÷ 121] x 100 = 40.5%
Formula
Percentage change = [(170 - 121) / 121] x 100
Subtract the new number by the original number
170 - 121 = 49
49 ÷ 121 = 0.4049586776859504
0.4049586776859504 x 100 = 40.5%