12.5% is the change from 8 to 9
Calculation steps:
[( 9 - 8 ) ÷ 8] x 100 = 12.5%
Formula
Percentage change = [(9 - 8) / 8] x 100
Subtract the new number by the original number
9 - 8 = 1
1 ÷ 8 = 0.125
0.125 x 100 = 12.5%
Example