-83.6% is the change from 866 to 142
Calculation steps:
[( 142 - 866 ) ÷ 866] x 100 = -83.6%
Formula
Percentage change = [(142 - 866) / 866] x 100
Subtract the new number by the original number
142 - 866 = -724
-724 ÷ 866 = -0.836027713625866
-0.836027713625866 x 100 = -83.6%