Checklist

• I have updated to the latest available Home Assistant version.
• I have cleared the cache of my browser.
• I have tried a different browser to see if it is related to my browser.
• I have tried reproducing the issue in safe mode to rule out problems with unsupported custom resources.

Describe the issue you are experiencing

The "trend chart" smooths data a bit too aggressively.

For example, given raw data like this:

A tile's trend chart renders it like this:

Describe the behavior you expected

I can tolerate and accept some smoothing, but in this case the final result is quite misleading. I expect it to look more like this:

Steps to reproduce the issue

1. Turn a dehumidifier (or any other device that uses a fixed amount of power) on and off a few times.
2. View the resulting trend graph.

What version of Home Assistant Core has the issue?

2025.9.0

What was the last working version of Home Assistant Core?

No response

In which browser are you experiencing the issue?

No response

Which operating system are you using to run this browser?

No response

State of relevant entities

Problem-relevant frontend configuration

features:
  - type: trend-graph
type: tile
features_position: inline
vertical: false
entity: sensor.dehumidifier_power
icon: mdi:air-humidifier
name: Dehumidifier

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Additional information

No response