-23.2% is the change from 638 to 490
Calculation steps:
[( 490 - 638 ) ÷ 638] x 100 = -23.2%
Formula
Percentage change = [(490 - 638) / 638] x 100
Subtract the new number by the original number
490 - 638 = -148
-148 ÷ 638 = -0.23197492163009403
-0.23197492163009403 x 100 = -23.2%