Best method for smoothing the data in a line graph

Hi ScottPat ,

As far as I know, currently Power BI doesn't support us to smooth line chart like the Excel. I think you need to create custom visuals. You may refer to attach file to try the "Advanced Line Chart".

Result:

Your demand is a good idea, while it is not supported to implement in Power BI currently.
You can vote up this idea for this function: "Smooth" Line Chart, Area Chart
Or you can submit a new idea to improve the Power BI.
It is a place for customers provide feedback about Microsoft Office products . What’s more, if a feedback is high voted there by other customers, it will be promising that Microsoft Product Team will take it into consideration when designing the next version in the future.

Best Regards,
Rico Zhou

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Hello ScottPat  and Anonymous 

From the july 2023 release - you can now change the line type to "smooth"-

See release note : Release note july 2023

or the snippet from the release note below to see how you can change line type to smooth:

Kind regards!

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