-31.5% is the change from 638 to 437
Calculation steps:
[( 437 - 638 ) ÷ 638] x 100 = -31.5%
Formula
Percentage change = [(437 - 638) / 638] x 100
Subtract the new number by the original number
437 - 638 = -201
-201 ÷ 638 = -0.31504702194357365
-0.31504702194357365 x 100 = -31.5%