-0.24% is the change from 850 to 848
Calculation steps:
[( 848 - 850 ) ÷ 850] x 100 = -0.24%
Formula
Percentage change = [(848 - 850) / 850] x 100
Subtract the new number by the original number
848 - 850 = -2
-2 ÷ 850 = -0.002352941176470588
-0.002352941176470588 x 100 = -0.24%