-28.24% is the change from 850 to 610
Calculation steps:
[( 610 - 850 ) ÷ 850] x 100 = -28.24%
Formula
Percentage change = [(610 - 850) / 850] x 100
Subtract the new number by the original number
610 - 850 = -240
-240 ÷ 850 = -0.2823529411764706
-0.2823529411764706 x 100 = -28.24%