-92.41% is the change from 870 to 66
Calculation steps:
[( 66 - 870 ) ÷ 870] x 100 = -92.41%
Formula
Percentage change = [(66 - 870) / 870] x 100
Subtract the new number by the original number
66 - 870 = -804
-804 ÷ 870 = -0.9241379310344827
-0.9241379310344827 x 100 = -92.41%