I think first you need to Clean your data, but coming to your questions, I used Rows those are in the PIC and Here it is. You can apply this solution to your dat ato get Call time where it is Null
If It Helps, Pl Mark it Helpful and CORRECT to Close Thread
Fix Time.twbx 19.5 KB
You're going to have a hard time doing this in Tableau (I know, I've tried). You are MUCH better off solving it in Excel, or somewhere else outside of Tableau.
Prep won't help you as you can't fill in ragged hierarchies (yet?) with Prep. You could create another column in the Excel file and populate it with a "previous value" calculation, and THEN bring it into Tableau. That's really manual though.
Perhaps someone else has had more luck than I have doing this in Tableau in a reliable way.