-98.05% is the change from 668 to 13
Calculation steps:
[( 13 - 668 ) ÷ 668] x 100 = -98.05%
Formula
Percentage change = [(13 - 668) / 668] x 100
Subtract the new number by the original number
13 - 668 = -655
-655 ÷ 668 = -0.9805389221556886
-0.9805389221556886 x 100 = -98.05%