-2.51% is the change from 638 to 622
Calculation steps:
[( 622 - 638 ) ÷ 638] x 100 = -2.51%
Formula
Percentage change = [(622 - 638) / 638] x 100
Subtract the new number by the original number
622 - 638 = -16
-16 ÷ 638 = -0.025078369905956112
-0.025078369905956112 x 100 = -2.51%