-83.91% is the change from 870 to 140
Calculation steps:
[( 140 - 870 ) ÷ 870] x 100 = -83.91%
Formula
Percentage change = [(140 - 870) / 870] x 100
Subtract the new number by the original number
140 - 870 = -730
-730 ÷ 870 = -0.8390804597701149
-0.8390804597701149 x 100 = -83.91%