-31.91% is the change from 937 to 638
Calculation steps:
[( 638 - 937 ) ÷ 937] x 100 = -31.91%
Formula
Percentage change = [(638 - 937) / 937] x 100
Subtract the new number by the original number
638 - 937 = -299
-299 ÷ 937 = -0.31910352187833513
-0.31910352187833513 x 100 = -31.91%