-75.71% is the change from 638 to 155
Calculation steps:
[( 155 - 638 ) ÷ 638] x 100 = -75.71%
Formula
Percentage change = [(155 - 638) / 638] x 100
Subtract the new number by the original number
155 - 638 = -483
-483 ÷ 638 = -0.7570532915360502
-0.7570532915360502 x 100 = -75.71%