-29.74% is the change from 908 to 638
Calculation steps:
[( 638 - 908 ) ÷ 908] x 100 = -29.74%
Formula
Percentage change = [(638 - 908) / 908] x 100
Subtract the new number by the original number
638 - 908 = -270
-270 ÷ 908 = -0.2973568281938326
-0.2973568281938326 x 100 = -29.74%