> For the complete documentation index, see [llms.txt](https://docs.ngsurvey.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ngsurvey.com/form-management/reports/report-builder/report-items/historical-trends.md).

# Historical Trends Chart

## 📆 What are historical trends ? 

The historical trends allows you to see over a given timeline the evolution of your respondent key satisfactions indicators. 

You can generate historical trends for following type of questions [NPS](/form-management/form-designer/questions/question-types/satisfaction-questions/net-promoter-score-r.md), [CSAT](/form-management/form-designer/questions/question-types/satisfaction-questions/csat-score.md), [CES](/form-management/form-designer/questions/question-types/satisfaction-questions/ces-score.md) or any question that has is enabled to support [rating](/form-management/form-designer/questions/rating.md). 

You may also use [sentiment index ](/form-management/reports/report-builder/report-items/sentiment-index.md)free text answers to monitor over time the sentiment of your respondents.  

Each column on the graph will show the index value for that particular date across all the respondents. The average index show in the title is calculated based on the full date range displayed on the graph.  

![](https://1025048312-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M8fLhS0bmfBRyq0HdUm%2F-MBZTFQvVTwGTTIQshPA%2F-MBZUcIRbWVUbAnavh5D%2Fimage.png?alt=media\&token=b4e695fb-b462-4b9a-bd54-77e42ddabb36)

## 📅  Set a custom timeline

The timeline of your trends can be setup by enabling the **filters** on your report item. The range of the timeline can be set from 6 hours, 12 hours, day, month to up of a year.

![](https://1025048312-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M8fLhS0bmfBRyq0HdUm%2F-MBZTFQvVTwGTTIQshPA%2F-MBZVe4m2ESesmZii24c%2Fimage.png?alt=media\&token=571ea281-a11e-476c-9394-801af94e97ba)

{% hint style="info" %}
The historical trend graph is also used by the [overview dashboard](/form-management/overview-reports.md).
{% endhint %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

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

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.ngsurvey.com/form-management/reports/report-builder/report-items/historical-trends.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

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.