-81.72% is the change from 870 to 159
Calculation steps:
[( 159 - 870 ) ÷ 870] x 100 = -81.72%
Formula
Percentage change = [(159 - 870) / 870] x 100
Subtract the new number by the original number
159 - 870 = -711
-711 ÷ 870 = -0.8172413793103448
-0.8172413793103448 x 100 = -81.72%