Calculate which item is most overdue, or list items by most overdue

I'm doing vehicle maintenance, and our vehicles are supposed to get serviced every 6 months. That's not always possible and some have gone longer than that. Also, it's also not always possible to service them in a specific order. For example, if a vehicle goes to the shop with an unrelated issue and we see that it's due or overdue for service, we go ahead and do it then even if it's not the "next" in line.

I track each of these services by vehicle number, date, mileage, and have a spot for notes.

The overall goal is to keep track in real-time of which vehicle is most overdue; that is, the vehicle that has gone the longest (by date) without being serviced. I've tried doing this with conditional formatting but it's not really what I need. A PivotTable was a little closer but still has to be sorted through manually.

The first sheet has a history of all of the services. The second sheet is a list of all vehicle numbers.

How can I call out which vehicles are most overdue at a glance?

Thank you so much!

Here is a simple formula that will determine if the date is older than 6 months

I'm sorry, I probably shouldn't say "real time" in this context. I only mean that each time the workbook is opened I would see at a glance which vehicle numbers are most overdue based on todays date and when each vehicle number was serviced last.

Each of those entries is a service date, so each vehicle number will have multiple entries going back a few years within that table.

so would it make sense to have a "Past Due" dashboard of sorts.. which would display 1 instance of the each vehicle that is past due?

Yes! And possibly also list the last service date for those past due vehicles, such that they could be sorted (or at least eyeballed) as to which is most overdue and should be next in for service.

I created a pivot table with the max dates and applied conditional formatting to highlight the ones that were older than 6 months..
take a look at the attached and see if that will help.

This is wonderful! Exactly what I need to see. Thank you so much.

No problem.