Coloring bars on Bar Chart

I need to create a bar chart to display project completion status. The length of the bar will indicate the percentage completed of the project. I have this working based upon the percentage entered into a spread sheet. I need to find a way to color the bar based upon whether the project is on time (green), at risk (yellow) or behind schedule (red). I can enter a value for the different status colors (ie:green=1, yellow=2, red=3) in the spread sheet. Is there a way to accomplish this. Thanks!