-48.35% is the change from 850 to 439
Calculation steps:
[( 439 - 850 ) ÷ 850] x 100 = -48.35%
Formula
Percentage change = [(439 - 850) / 850] x 100
Subtract the new number by the original number
439 - 850 = -411
-411 ÷ 850 = -0.4835294117647059
-0.4835294117647059 x 100 = -48.35%