-35.75% is the change from 993 to 638
Calculation steps:
[( 638 - 993 ) ÷ 993] x 100 = -35.75%
Formula
Percentage change = [(638 - 993) / 993] x 100
Subtract the new number by the original number
638 - 993 = -355
-355 ÷ 993 = -0.35750251762336355
-0.35750251762336355 x 100 = -35.75%