> For the complete documentation index, see [llms.txt](https://docs.exploratory.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.exploratory.io/visualization/types/singlevalue.md).

# Number

You can show a single, aggregated number. It is good for tracking a specific number, and it is good for using it in Dashborads.

![](/files/-M4oNBJ7gylxP7a919TK)

## Column Assignments

* Value - Assign a data column you want to show. It can be in any data types.

## Changing the caption text

You can rename the chart then the same name comes up as a caption.

![](/files/-M4oNBJ9HdveEcVP3P0B)

## Custom Function

You can use the Custom Function feature to define your own aggregation function. See [Custom Function](https://github.com/exploratory-io/book/blob/master/viz/custom-function.md) for the detail.

## Layout Configuration

* Default Value - The default text value used when the data is NA. The default is ''.

Take a look at [Layout Configuration](/visualization/features/layout.md) on how to configure the layout and format.