-79.31% is the change from 870 to 180
Calculation steps:
[( 180 - 870 ) ÷ 870] x 100 = -79.31%
Formula
Percentage change = [(180 - 870) / 870] x 100
Subtract the new number by the original number
180 - 870 = -690
-690 ÷ 870 = -0.7931034482758621
-0.7931034482758621 x 100 = -79.31%