-6.25% is the change from 128 to 120
Calculation steps:
[( 120 - 128 ) ÷ 128] x 100 = -6.25%
Formula
Percentage change = [(120 - 128) / 128] x 100
Subtract the new number by the original number
120 - 128 = -8
-8 ÷ 128 = -0.0625
-0.0625 x 100 = -6.25%