-50.82% is the change from 669 to 329
Calculation steps:
[( 329 - 669 ) ÷ 669] x 100 = -50.82%
Formula
Percentage change = [(329 - 669) / 669] x 100
Subtract the new number by the original number
329 - 669 = -340
-340 ÷ 669 = -0.5082212257100149
-0.5082212257100149 x 100 = -50.82%