9.52% is the change from 21 to 23
Calculation steps:
[( 23 - 21 ) ÷ 21] x 100 = 9.52%
Formula
Percentage change = [(23 - 21) / 21] x 100
Subtract the new number by the original number
23 - 21 = 2
2 ÷ 21 = 0.09523809523809523
0.09523809523809523 x 100 = 9.52%