Active Report Pie Charts - Displaying Percentages

[NiceCube]

Hi All,

As the Subject suggests I'm haing a problem with a pie chart on an active report.  The pie is showing numbers, rather than percentages.  I'm having one of those days when nothing seems straightforward.  The total column in the data is just a '1' and I have a Pass/Fail column where, based on logic, it's either a Pass or Fail.  Nothing complicated, you may think (I did), but I'm fairly new to charting.

Can anyone advise?

Thanks,  Rich