Can we color code column with different colors?

I want to color code the cells/field value with various colors. Like this below formula:

IF [NPS_Value] >= 20 THEN "GREEN" ELSEIF [NPS_Value] >= 10 THEN "GREEN" ELSEIF [NPS_Value] >= 5 THEN "PINK" ELSEIF [NPS_Value] >= 2 THEN "ORANGE"

ELSEIF [NPS_Value] >= -2 THEN "YELLOW" ELSEIF [NPS_Value] >= -5 THEN "BROWN" ELSEIF [NPS_Value] >= -10 THEN "RED"  END

Problem with this is, it doesn't assign right color to this cell. Any idea to this please? Any help to this is appreciated.