-61.86% is the change from 839 to 320
Calculation steps:
[( 320 - 839 ) ÷ 839] x 100 = -61.86%
Formula
Percentage change = [(320 - 839) / 839] x 100
Subtract the new number by the original number
320 - 839 = -519
-519 ÷ 839 = -0.6185935637663885
-0.6185935637663885 x 100 = -61.86%