-38.56% is the change from 638 to 392
Calculation steps:
[( 392 - 638 ) ÷ 638] x 100 = -38.56%
Formula
Percentage change = [(392 - 638) / 638] x 100
Subtract the new number by the original number
392 - 638 = -246
-246 ÷ 638 = -0.38557993730407525
-0.38557993730407525 x 100 = -38.56%