Tooltips showing extra text

[Ross Burton]

Hi,

I've an areachart with multiple columns and have set focusTarget:category so the tooltips show the values for all of the columns at that X value.  However, I'd like to add an extra bit of text to the tooltip without replacing the display of the value.  Is this possible? It looks like setting  a tooltip column replaces the value display, and I can't see a way to add a columm that appears in the tooltips but isn't represented on the chart.

Cheers,

Ross