-48.59% is the change from 638 to 328
Calculation steps:
[( 328 - 638 ) ÷ 638] x 100 = -48.59%
Formula
Percentage change = [(328 - 638) / 638] x 100
Subtract the new number by the original number
328 - 638 = -310
-310 ÷ 638 = -0.48589341692789967
-0.48589341692789967 x 100 = -48.59%