# 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.

![](https://2850417076-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M4HLCK3olgduYoe3RVS%2F-M4oMvCUDQwHTJ0eWi_f%2F-M4oNBJ7gylxP7a919TK%2Fsinglevalue2.png?generation=1586795475578797\&alt=media)

## 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.

![](https://2850417076-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M4HLCK3olgduYoe3RVS%2F-M4oMvCUDQwHTJ0eWi_f%2F-M4oNBJ9HdveEcVP3P0B%2Fsinglevalue1.png?generation=1586795475669977\&alt=media)

## 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](https://docs.exploratory.io/visualization/features/layout) on how to configure the layout and format.