> ## Documentation Index
> Fetch the complete documentation index at: https://help.dingtalk.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Reference Lines

> This page explains how to configure multiple reference lines in various charts (such as Column, Line, and more), covering the use of the data settings panel, customization of reference line styles, and worked examples that demonstrate how to configure reference lines at different positions and in different styles.

## 1. Overview

Configure chart reference lines, with support for **multiple** lines at the same time. Supported charts: **Column, Line, Column-Line combo, and Scatter**.

Reference lines

## 2. Reference Line — Data Settings Panel

### 2.1 Aggregation

For the reference line value, you can use a regular field with aggregation, or add a formula field directly.

Configure a reference line

### 2.2 Reference Line Style

* Location: choose between the left Y-axis value or the X-axis.
* Content: title and value, selected by default.
* Reference line style: change the color, configure a dashed style, and set the line width.
* Text settings: set the font size, color, and display position.

Configure the reference line style

## 3. Examples

### 3.1 Example 1: Place the Reference Line on the X-Axis and Display It as a Dashed Line

1. When setting the reference line value, make sure it corresponds to X-axis content.

Configure a formula reference line

2. Set the reference line location to the X-axis, then configure the color and dashed style.

Configure the reference line style

Preview

### 3.2 Example 2: Place the Reference Line on the Right Y-Axis

1. Configure the reference line value. Here, a formula field is used as an example:

Configure a formula reference line

2. Set the reference line location to the right Y-axis:

Configure the reference line style

### 3.3 Example 3: Calculate the Average of Employee ID (Employee ID / Month)

Configure the reference line values.

Left reference line: COUNTDISTINCT(Employee ID)/COUNTDISTINCT(DATEFORMAT(Date,"yyyy-MM"))

Right reference line: COUNT(Employee ID)/COUNTDISTINCT(DATEFORMAT(Date,"yyyy-MM"))

Configure two formula-based reference lines (left and right)