-99.7% is the change from 665 to 2
Calculation steps:
[( 2 - 665 ) ÷ 665] x 100 = -99.7%
Formula
Percentage change = [(2 - 665) / 665] x 100
Subtract the new number by the original number
2 - 665 = -663
-663 ÷ 665 = -0.9969924812030075
-0.9969924812030075 x 100 = -99.7%