-31.88% is the change from 643 to 438
Calculation steps:
[( 438 - 643 ) ÷ 643] x 100 = -31.88%
Formula
Percentage change = [(438 - 643) / 643] x 100
Subtract the new number by the original number
438 - 643 = -205
-205 ÷ 643 = -0.3188180404354588
-0.3188180404354588 x 100 = -31.88%