-77.19% is the change from 171 to 39
Calculation steps:
[( 39 - 171 ) ÷ 171] x 100 = -77.19%
Formula
Percentage change = [(39 - 171) / 171] x 100
Subtract the new number by the original number
39 - 171 = -132
-132 ÷ 171 = -0.7719298245614035
-0.7719298245614035 x 100 = -77.19%