Charting Tool Formula Support
The Charting Tool includes formula support for setting styles to different chart elements. Formulas can be used to change the styles applied to specific points in a chart. This applies on a "per series" basis, and any number of formulas can be used per series, allowing you to modify most of the styles that can normally be applied to any given point in the series.
If using formulas to customize colors, see Colors.
Chart Types that Support Formulas
Because formulas are used to style different individual points within a chart, they do not apply to chart types that don't have individual points mapped in them (such as Area charts). They also do not apply to chart types in which their use would possibly make the chart confusing (such as Pie charts), or that are very standardized (Pareto Charts). Here is a list of the chart types that can use formulas:
- Bar
- Stacked Bar
- Column
- Stacked Column
- Tornado
- Box and Whisker
- Bubble
- Scatter
- Combination Column and Line chart, but only for the Column series
Using a Formula in a Chart
Under Setup Chart Appearance:, select the Series Style option.
Set the Style Mode to Formula.
A grid appears with the value Default. The styling matches the series styling default, but can be edited. Any points the do not match a formula's condition are style to match the Default style. This is not true for Scatter and Bubble chart types.
Click the 
button to add a formula. You can either type the formula in the box, or click Edit to display the Formula Editor.
Click the 
button to delete a selected formula.
Reorder formulas with the up and down arrows. Formulas are applied in the order they appear in the grid.
With a formula selected, configure the other Series Style parameters to set the style on the chart elements.
From the Formula grid, the Legend field is automatically populated with the formula. You can edit the text that displays on the legend.
The Chart Legend
From the Formula Grid Control there is a column marked Legend. The text in this column is what will be displayed on the Legend.
Legend display is set from the Legend Panel, Show Legend has a Yes or No property.
By default, the Legend Column is populated with the Formula, but it can be edited by clicking inside the field and typing the desired legend text.
If a formula is not applied to the points in the chart, then there will be no legend item for that formula. Likewise, if all of the points in the chart are styled by formulas, the Default element will not display on the chart or legend.
Additional Variables
From the Variables tab on the formula editor, there are two additional fields that you can use in your formulas. They are as follows:
Plot Position
This variable represents the "row" for Bar or Tornado charts, or the "column" for Column and Box and Whisker charts. They are applied "out" from the origin, as follows:
For Scatter and Bubble charts, PlotPosition can be used as a substitute for the X axis (horizontal) field, similar to the CurrentField variable.
Current Field
CurrentField can be used as a substitute for whatever field is selected for the series in question.
CurrentField Special Considerations
Box and Whisker: since there are actually five fields required per plot element on the chart, CurrentField obviously cannot be applied to all the fields selected. If it is specified in this chart type, it will apply to the "Median." The other four fields ("Maximum", "UpperQuartile", "LowerQuartile", and "Minimum") do not have substitutes for formulas.
Scatter and Bubble: CurrentField can be used as a substitute for the Y axis (vertical) field. Therefore, for these two chart types, the combination of PlotPosition and CurrentField can be used as substitutes for both axes.
Default Exception
Scatter and Bubble charts behave differently than other chart types when a formula is applied to the series style.
When in Standard style mode, the points receive different colors based on a palette of colors available.
In the Formula mode, the default is only one color. Therefore, points on those charts that do not have other formulas applied to them will not cycle through different colors, but instead will all be the one color selected for the "default" entry. This keeps these chart types functioning in the same fashion as the other chart types that use formulas.