git – How to calculate lead time to deploy most efficiently?

I want to calculate the lead time to deploy of a team in Azure DevOps.

Lead time is the amount of time it takes a commit to get into production. Thus the code must reach the master branch beforde deployment.

However, following every commit from its original feature branch into the master from where it gets deployed sounds very clumsy.

So my question is: Is my complicated thinking necessary or is there a more efficient way of calculating the timespan between first commit in feature branch and merge into master where this commit would transitively be also part of?

Thank you very much in advance.