-80.25% is the change from 866 to 171
Calculation steps:
[( 171 - 866 ) ÷ 866] x 100 = -80.25%
Formula
Percentage change = [(171 - 866) / 866] x 100
Subtract the new number by the original number
171 - 866 = -695
-695 ÷ 866 = -0.8025404157043879
-0.8025404157043879 x 100 = -80.25%