-87.43% is the change from 668 to 84
Calculation steps:
[( 84 - 668 ) ÷ 668] x 100 = -87.43%
Formula
Percentage change = [(84 - 668) / 668] x 100
Subtract the new number by the original number
84 - 668 = -584
-584 ÷ 668 = -0.874251497005988
-0.874251497005988 x 100 = -87.43%