-48.39% is the change from 620 to 320
Calculation steps:
[( 320 - 620 ) ÷ 620] x 100 = -48.39%
Formula
Percentage change = [(320 - 620) / 620] x 100
Subtract the new number by the original number
320 - 620 = -300
-300 ÷ 620 = -0.4838709677419355
-0.4838709677419355 x 100 = -48.39%