14.29% is the change from 21 to 24
Calculation steps:
[( 24 - 21 ) ÷ 21] x 100 = 14.29%
Formula
Percentage change = [(24 - 21) / 21] x 100
Subtract the new number by the original number
24 - 21 = 3
3 ÷ 21 = 0.14285714285714285
0.14285714285714285 x 100 = 14.29%