-34.56% is the change from 489 to 320
Calculation steps:
[( 320 - 489 ) ÷ 489] x 100 = -34.56%
Formula
Percentage change = [(320 - 489) / 489] x 100
Subtract the new number by the original number
320 - 489 = -169
-169 ÷ 489 = -0.3456032719836401
-0.3456032719836401 x 100 = -34.56%