-10% is the change from 120 to 108
Calculation steps:
[( 108 - 120 ) ÷ 120] x 100 = -10%
Formula
Percentage change = [(108 - 120) / 120] x 100
Subtract the new number by the original number
108 - 120 = -12
-12 ÷ 120 = -0.1
-0.1 x 100 = -10%
Example