# 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.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.exploratory.io/visualization/types/singlevalue.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.