-97.01% is the change from 668 to 20
Calculation steps:
[( 20 - 668 ) ÷ 668] x 100 = -97.01%
Formula
Percentage change = [(20 - 668) / 668] x 100
Subtract the new number by the original number
20 - 668 = -648
-648 ÷ 668 = -0.9700598802395209
-0.9700598802395209 x 100 = -97.01%