Since the calculation should compare data from different rows,
LOD expressions could be of little (if any) use.
But one could use Table Calculations instead.
Please find the attached.
Thank you very much, Yuri. I had worked through it and developed a similar calculation. Is there a way to generate the same calculation without having to organize the data into a table? i.e. the data would be loaded/refreshed and there would be an aggregate calculation (avg, min, max etc) for Turnaround time?
Even if there's a way, I'm not aware of it, sorry.
One can rearrange pills on a view,
choose a different viz type,
Hide (not Filter out) some Marks.
But one couldn't change the Dimensions on a view,
so the Visual Level-Of-Detail (VizLOD) to remain intact --
for the Table Calculations to work as expected.
If it could be possible to avoid Table Calcs
and make everything work with aggregates
(all without radically changing the datasource),
I would let you know immediately.