-70.53% is the change from 638 to 188
Calculation steps:
[( 188 - 638 ) ÷ 638] x 100 = -70.53%
Formula
Percentage change = [(188 - 638) / 638] x 100
Subtract the new number by the original number
188 - 638 = -450
-450 ÷ 638 = -0.7053291536050157
-0.7053291536050157 x 100 = -70.53%