-48.51% is the change from 639 to 329
Calculation steps:
[( 329 - 639 ) ÷ 639] x 100 = -48.51%
Formula
Percentage change = [(329 - 639) / 639] x 100
Subtract the new number by the original number
329 - 639 = -310
-310 ÷ 639 = -0.48513302034428796
-0.48513302034428796 x 100 = -48.51%