-94.21% is the change from 639 to 37
Calculation steps:
[( 37 - 639 ) ÷ 639] x 100 = -94.21%
Formula
Percentage change = [(37 - 639) / 639] x 100
Subtract the new number by the original number
37 - 639 = -602
-602 ÷ 639 = -0.9420970266040689
-0.9420970266040689 x 100 = -94.21%