-89.95% is the change from 866 to 87
Calculation steps:
[( 87 - 866 ) ÷ 866] x 100 = -89.95%
Formula
Percentage change = [(87 - 866) / 866] x 100
Subtract the new number by the original number
87 - 866 = -779
-779 ÷ 866 = -0.8995381062355658
-0.8995381062355658 x 100 = -89.95%