Passing token to chart overlay

[mdunnavant]

I've searched and searched on this and it's time to just ask the question.

I want to create a simple transaction count bar overlayed with the average duration line.  I can do this when hard setting the transaction name. 

However, when I try to generate an overlay using a dropdown of transaction names there is no overlay.  I feel like I'm just not passing a correctly formatted token to charting.chart.overlayFields option.

I've tried,

• <option name="charting.chart.overlayFields">"avg(duration):" $ID$</option>
• <option name="charting.chart.overlayFields">$ID$</option>
• <option name="charting.chart.overlayFields">avg(duration): $ID$</option>
• and probably dozens more as I'm throwing darts.

Any ideas here?