-31.62% is the change from 642 to 439
Calculation steps:
[( 439 - 642 ) ÷ 642] x 100 = -31.62%
Formula
Percentage change = [(439 - 642) / 642] x 100
Subtract the new number by the original number
439 - 642 = -203
-203 ÷ 642 = -0.3161993769470405
-0.3161993769470405 x 100 = -31.62%