-49.22% is the change from 638 to 324
Calculation steps:
[( 324 - 638 ) ÷ 638] x 100 = -49.22%
Formula
Percentage change = [(324 - 638) / 638] x 100
Subtract the new number by the original number
324 - 638 = -314
-314 ÷ 638 = -0.49216300940438873
-0.49216300940438873 x 100 = -49.22%