Thank you for help,

Got the point and it works.

Thanks again.

 setting the ColorModel.AlphaLevel = 0 should do it.  if you have a GradientEffect in the Effects collection, remove that as well.

Hello,

I am too facing the same problem how to remove the  outer color bar when "ShowCompletePercentages" proprty set to true,

If any one have solution please post it.

Thank you in advance. 

Coder said:

How to get rid of that filled rectangle showing Completion percentage? I want to display my completion status with two coloured bar not that filled rectangle in the bar. 

If I understand correctly, you are trying to remove the outer color bar and just leave the two bars that show the percent complete and percent remaining.  What I ended up doing was setting the outer bar alpha level to 0 (zero) so it is transparent.

    <ColorModel AlphaLevel="0" />
    <GanttChart>
        <EmptyPercentagesPE Fill="AliceBlue" StrokeWidth="1" StrokeOpacity="70" />
        <CompletePercentagesPE Fill="#558FAA" StrokeWidth="1" StrokeOpacity="70" />
    </GanttChart>

Note that this still draws the outer bar and it still takes up space, but you don’t see it so you might want to set the item spacing to 0 (zero).
    GanttChart-ItemSpacing="0"

 If anyone has a better way, please post as this seems to be a bit of a kluge.

How to get rid of that filled rectangle showing Completion percentage? I want to display my completion status with two coloured bar not that filled rectangle in the bar.