-86.78% is the change from 870 to 115
Calculation steps:
[( 115 - 870 ) ÷ 870] x 100 = -86.78%
Formula
Percentage change = [(115 - 870) / 870] x 100
Subtract the new number by the original number
115 - 870 = -755
-755 ÷ 870 = -0.867816091954023
-0.867816091954023 x 100 = -86.78%