-57.68% is the change from 638 to 270
Calculation steps:
[( 270 - 638 ) ÷ 638] x 100 = -57.68%
Formula
Percentage change = [(270 - 638) / 638] x 100
Subtract the new number by the original number
270 - 638 = -368
-368 ÷ 638 = -0.5768025078369906
-0.5768025078369906 x 100 = -57.68%