-87.28% is the change from 668 to 85
Calculation steps:
[( 85 - 668 ) ÷ 668] x 100 = -87.28%
Formula
Percentage change = [(85 - 668) / 668] x 100
Subtract the new number by the original number
85 - 668 = -583
-583 ÷ 668 = -0.8727544910179641
-0.8727544910179641 x 100 = -87.28%