-98.71% is the change from 850 to 11
Calculation steps:
[( 11 - 850 ) ÷ 850] x 100 = -98.71%
Formula
Percentage change = [(11 - 850) / 850] x 100
Subtract the new number by the original number
11 - 850 = -839
-839 ÷ 850 = -0.9870588235294118
-0.9870588235294118 x 100 = -98.71%