-99.53% is the change from 850 to 4
Calculation steps:
[( 4 - 850 ) ÷ 850] x 100 = -99.53%
Formula
Percentage change = [(4 - 850) / 850] x 100
Subtract the new number by the original number
4 - 850 = -846
-846 ÷ 850 = -0.9952941176470588
-0.9952941176470588 x 100 = -99.53%