-97.6% is the change from 668 to 16
Calculation steps:
[( 16 - 668 ) ÷ 668] x 100 = -97.6%
Formula
Percentage change = [(16 - 668) / 668] x 100
Subtract the new number by the original number
16 - 668 = -652
-652 ÷ 668 = -0.9760479041916168
-0.9760479041916168 x 100 = -97.6%