Putting a Value on Your Value: Quantifying Vanguard Advisor Alpha that calculated an advisor’s value-add at “about 3%.” In a 2018 Canadian version of the study, Vanguard found that behavioral coaching added 150 basis points in value; wealth management, 42 to 88 (with rebalancing valued at 42 basis points alone); and portfolio construction, 86 to 128.

Here is a link to a similar study to the one by Vanguard.

Here is the actual link to the Vanguard study with all the gory details. It’s a white paper.

https://advisors.vanguard.com/iwe/pdf/ISGQVAA.pdf