-39.78% is the change from 646 to 389
Calculation steps:
[( 389 - 646 ) ÷ 646] x 100 = -39.78%
Formula
Percentage change = [(389 - 646) / 646] x 100
Subtract the new number by the original number
389 - 646 = -257
-257 ÷ 646 = -0.3978328173374613
-0.3978328173374613 x 100 = -39.78%