-68.03% is the change from 638 to 204
Calculation steps:
[( 204 - 638 ) ÷ 638] x 100 = -68.03%
Formula
Percentage change = [(204 - 638) / 638] x 100
Subtract the new number by the original number
204 - 638 = -434
-434 ÷ 638 = -0.6802507836990596
-0.6802507836990596 x 100 = -68.03%