Help - Pie Chart slice colours

[scorerp]

I have a question about the colours of pie chart slices, which I'm sure has a simple resolution.

I have created a number of pie charts within one worksheet and have formatted them so that when a value is zero it is not shown in the pie chart (so that the data lables don't show). The problem is that there are originally four categories, which have to be coloured Black, Red, Amber and Green. If one of these categories are zero, and is subsequently removed from the chart it changes the colours of the slices.

For example, if black is zero, the red slice becomes black, amber becomes red and green becomes amber. The correct colouring of the slices is vital as it is linked to risk levels.

How can I still remove the slices so that the data labels don't show whil retaining the correct formatting?

To remove the zero's I used the suggestion in this thread:

http://www.mrexcel.com/forum/showthread.php?t=557662&highlight=hide+charts

I'm using Excel 2003.

Thanks

Thanks