-77.46% is the change from 639 to 144
Calculation steps:
[( 144 - 639 ) ÷ 639] x 100 = -77.46%
Formula
Percentage change = [(144 - 639) / 639] x 100
Subtract the new number by the original number
144 - 639 = -495
-495 ÷ 639 = -0.7746478873239436
-0.7746478873239436 x 100 = -77.46%