-98.58% is the change from 635 to 9
Calculation steps:
[( 9 - 635 ) ÷ 635] x 100 = -98.58%
Formula
Percentage change = [(9 - 635) / 635] x 100
Subtract the new number by the original number
9 - 635 = -626
-626 ÷ 635 = -0.9858267716535433
-0.9858267716535433 x 100 = -98.58%