-87.32% is the change from 678 to 86
Calculation steps:
[( 86 - 678 ) ÷ 678] x 100 = -87.32%
Formula
Percentage change = [(86 - 678) / 678] x 100
Subtract the new number by the original number
86 - 678 = -592
-592 ÷ 678 = -0.8731563421828908
-0.8731563421828908 x 100 = -87.32%