-39.16% is the change from 646 to 393
Calculation steps:
[( 393 - 646 ) ÷ 646] x 100 = -39.16%
Formula
Percentage change = [(393 - 646) / 646] x 100
Subtract the new number by the original number
393 - 646 = -253
-253 ÷ 646 = -0.39164086687306504
-0.39164086687306504 x 100 = -39.16%