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Add a target line, event marker or caption to a chart

Anyone who can edit the dashboard · Updated 8 Nov 2026

A chart's edit panel can pin a labelled line at a value, a marker on one point of the x-axis, and a caption under the chart. Click a chart in the dashboard editor to open its edit panel; anyone who can edit the dashboard can add them. For colours, formats and axes, see Style a dashboard chart.

Add a target line or event marker to a chart

The Annotations section pins a labelled line at a value (a target or an average), or a labelled marker on one point of the x-axis (a launch, a price change). It's on Bar, Bar (H), Line, Area, Grouped bar, Combo, Stacked bar and Stacked area charts.

ButtonAddsFields
+ Reference lineA Reference row: a horizontal lineValue (a number) and Label
+ EventAn Event row: a marker on one x-axis pointA point (Pick a date) and a Label
  • The event's point list holds the labels on the chart's own x-axis, so an event can only sit on a point the chart shows. + Event is disabled when the chart has no x-axis labels.
  • Every row has a Color: Default, Brand, Positive, Negative, Warning or Info. The colours follow the dashboard theme.
  • × removes a row.
  • On a chart with more than one axis, each row also asks "Which axis this value belongs to".

The line and label redraw as you type.

Example: to mark a sales target of 50,000:

  1. Click + Reference line.
  2. Set Value to 50000.
  3. Set Label to "Target".
  4. Set Color to Positive.

Add a caveat or source caption under a chart

A caption is one or two lines of text under a single chart. It says what the chart leaves out or where its numbers come from.

  1. Near the bottom of the panel, tick Add a caption.
  2. Pick the kind: Caveat ("A limit on what the numbers cover", the default) or Source ("Where the data came from").
  3. Type the text (placeholder "Excludes Head Office…").

Bold, Italic and Link buttons format it: "One or two lines, under the chart. bold, italic and links are supported."

Insert values that stay current in a caption

The { } button ("Insert something the board fills in") adds a value the dashboard keeps current. It appears when the dashboard has these facts:

ValueWhat it shows
{updated}When this board was last built
{rows}How many rows it covers
{range}The period the data covers
{dataset}The dataset this board reads
{filters}What the reader has filtered to

Untick Add a caption to delete the caption. For notes about the whole dashboard rather than one chart, use a text block.

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