-20.31% is the change from 389 to 310
Calculation steps:
[( 310 - 389 ) ÷ 389] x 100 = -20.31%
Formula
Percentage change = [(310 - 389) / 389] x 100
Subtract the new number by the original number
310 - 389 = -79
-79 ÷ 389 = -0.20308483290488433
-0.20308483290488433 x 100 = -20.31%