Sankey Chart

By default, standard Sankey visuals (like the Microsoft one) calculate node height based purely on the sum of the links (flows) entering or exiting that node. They do not natively support an independent "size" field to scale the node differently from the flow itself. However, you can achieve this effect using a workaround or by switching to a more advanced custom visual.

Option 1: The "Dummy Flow" Workaround (For your current visual)
If you must stick with version 3.4.5.0, you cannot directly change the node height logic. However, you can manipulate the data to force the node to be larger.

The Concept: Create a "dummy" destination node that captures the extra value you want to represent.

The Fix:

Create a calculated table or measure that adds the difference between your "Actual Value" and the "Flow Value" as a new flow to a hidden or dummy node.

This increases the total volume passing through the source node, making it taller, while the flow to the "real" next step remains accurate.

Note: This can make the chart look cluttered, so it's often not the preferred method.

Option 2: Switch to "Charticulator" or "Deneb" (Recommended)
If you need precise control where the node height represents a metric (like "Total Capacity") while the link width represents another (like "Used Capacity"), you are better off building a custom Sankey.

Charticulator: This Microsoft tool allows you to build custom visuals without coding. You can drag your "Actual Value" field to the Height attribute of the node glyph, unlinking it from the link width.

Deneb (Vega-Lite): This is for advanced users but offers 100% customization. You can explicitly code the y and height channels of your nodes based on your specific measure.

Option 3: Use the "Sankey Chart by Daviz" (Third-Party)
There are other custom visuals in the AppSource marketplace that offer more settings.

Search for HTML Content or other advanced Sankey visuals like Sankey Chart by Daviz.

Some premium versions of these charts allow you to define "Node Weight" separately from "Link Weight."

Recommendation: Since feature requests for specific visual versions (like 3.4.5.0) are controlled by the developer (Microsoft), they likely won't add this retroactively. I recommend trying Charticulator for a no-code way to build exactly the specific node-sizing logic you need.

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