-73.71% is the change from 639 to 168
Calculation steps:
[( 168 - 639 ) ÷ 639] x 100 = -73.71%
Formula
Percentage change = [(168 - 639) / 639] x 100
Subtract the new number by the original number
168 - 639 = -471
-471 ÷ 639 = -0.7370892018779343
-0.7370892018779343 x 100 = -73.71%