> 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.  

![](/files/-MBZUcIRbWVUbAnavh5D)

## 📅  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.

![](/files/-MBZVe4m2ESesmZii24c)

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


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