23.46% is the change from 81 to 100
Calculation steps:
[( 100 - 81 ) ÷ 81] x 100 = 23.46%
Formula
Percentage change = [(100 - 81) / 81] x 100
Subtract the new number by the original number
100 - 81 = 19
19 ÷ 81 = 0.2345679012345679
0.2345679012345679 x 100 = 23.46%