-23.53% is the change from 170 to 130
Calculation steps:
[( 130 - 170 ) ÷ 170] x 100 = -23.53%
Formula
Percentage change = [(130 - 170) / 170] x 100
Subtract the new number by the original number
130 - 170 = -40
-40 ÷ 170 = -0.23529411764705882
-0.23529411764705882 x 100 = -23.53%