I've been trying to figure this out, and I don't have a solution yet.
I created a simple dashboard that uses a timestamp to show when a patient checks into the emergency department. So, if you have 100 patients who check in between 10 and 11 AM, the 10 AM block will show 100; if you have another 100 that check in between 11 AM and noon, the 11 AM block will show 100. This is all well and good, but what I'd like to show is how many patients are in the ER past that first hour.
100 patients check in at 10 AM. 20 of these them stay an additional hour.
100 patients check in at 11AM. 30 of these stay an additional hour.
0 patients check in at noon.
So, 10 AM block would show 100 patients. 11 AM block shoes 120 patients. Noon block shows 30 patients. Does that make sense?
The goal is to give a more accurate picture of how busy the ER is throughout the day, because many patients will be in the ER for more than 4 hours. I just can't figure out how to display this, or how to create a dimension that represents this.
I can't be too sure without seeing the data (if you can share a .twbx, perhaps replicating your work with anonymised data, that would be great!) but I think a method like the one here would help: Showing Records That Fall Within a Period of Time | Tableau Software