-97.14% is the change from 665 to 19
Calculation steps:
[( 19 - 665 ) ÷ 665] x 100 = -97.14%
Formula
Percentage change = [(19 - 665) / 665] x 100
Subtract the new number by the original number
19 - 665 = -646
-646 ÷ 665 = -0.9714285714285714
-0.9714285714285714 x 100 = -97.14%