-32.75% is the change from 171 to 115
Calculation steps:
[( 115 - 171 ) ÷ 171] x 100 = -32.75%
Formula
Percentage change = [(115 - 171) / 171] x 100
Subtract the new number by the original number
115 - 171 = -56
-56 ÷ 171 = -0.32748538011695905
-0.32748538011695905 x 100 = -32.75%