-48.34% is the change from 331 to 171
Calculation steps:
[( 171 - 331 ) ÷ 331] x 100 = -48.34%
Formula
Percentage change = [(171 - 331) / 331] x 100
Subtract the new number by the original number
171 - 331 = -160
-160 ÷ 331 = -0.48338368580060426
-0.48338368580060426 x 100 = -48.34%