-33.54% is the change from 638 to 424
Calculation steps:
[( 424 - 638 ) ÷ 638] x 100 = -33.54%
Formula
Percentage change = [(424 - 638) / 638] x 100
Subtract the new number by the original number
424 - 638 = -214
-214 ÷ 638 = -0.335423197492163
-0.335423197492163 x 100 = -33.54%