-20.65% is the change from 804 to 638
Calculation steps:
[( 638 - 804 ) ÷ 804] x 100 = -20.65%
Formula
Percentage change = [(638 - 804) / 804] x 100
Subtract the new number by the original number
638 - 804 = -166
-166 ÷ 804 = -0.2064676616915423
-0.2064676616915423 x 100 = -20.65%