Chart Targets

Each chart target shows the following characteristics:

A non-adjustable input name e.g. primary, value, size, etc.
Some targets also have a 'Properties' button, that is generally meaningful even if no source has been applied
For targets that have no source assigned:
- some sort of drop-zone indicator e.g. 'Drop items here'
For targets that do have a source assigned:
- the column source name i.e. column name
- an icon, indicating the column source type
- depending on the source, a drop-down arrow to allow data aggregation, see 'Pivoting' below

Primary	Source identifies the row being shown.	Properties actually shows primary axis properties.
Values	Source shows the value of the row.	Properties shows primary axis properties, with a few series properties tacked on. Special case for hero text - has its own properties page here.
End Values	Source shows the other end of a value range.
Size	Adjusts the size of the data point (bubble chart).
Associate	Identifies the related data, for hierarchies/networks.
Colour	Unique values get assigned unique colours.	Or if the report column has conditional formatting, this can be activated in the colour properties.
Text	Show a data label with this source value on all data points.
Image	The background is painted with this image.	Can only be assigned a report image column.
Symbol	Unique values get assigned unique symbols, until all are exhausted.

Drag and drop is the only way to assign chart sources to chart targets.

A source can be dragged from the toolbox to a target. This creates a new chart source entity
The same source can be dropped in multiple places.
Sources cannot be removed from the toolbar.
A source can be dragged from one chart target to another. This creates a copy of the chart source entity
A source can be removed from a chart target by dragging it onto the background