50% is the change from 14 to 21
Calculation steps:
[( 21 - 14 ) ÷ 14] x 100 = 50%
Formula
Percentage change = [(21 - 14) / 14] x 100
Subtract the new number by the original number
21 - 14 = 7
7 ÷ 14 = 0.5
0.5 x 100 = 50%
Example