12.42% is the change from 161 to 181
Calculation steps:
[( 181 - 161 ) ÷ 161] x 100 = 12.42%
Formula
Percentage change = [(181 - 161) / 161] x 100
Subtract the new number by the original number
181 - 161 = 20
20 ÷ 161 = 0.12422360248447205
0.12422360248447205 x 100 = 12.42%