-14.91% is the change from 999 to 850
Calculation steps:
[( 850 - 999 ) ÷ 999] x 100 = -14.91%
Formula
Percentage change = [(850 - 999) / 999] x 100
Subtract the new number by the original number
850 - 999 = -149
-149 ÷ 999 = -0.14914914914914915
-0.14914914914914915 x 100 = -14.91%