Help! Trying to calculate time differences between two different lists of timestamps!

[winslowmargot]

Hi! I have two lists of dates for a project, one is the Maintenance Dates and one is the Production Dates. I'm trying to figure out for each Production Date, how long has it been since the last Maintenance Date. The Maintenance Dates will be far less frequent than Production Dates, obviously, but there are a lot of them so it would be way easier to have a formula to calculate this delta. Anyone have any suggestions?

 

[JumpingCrab]

How is this data organized? In rows / columns? Can you give an example?

 

[winslowmargot]

Basically I have 4 columns: Equipment Name, Widget Lot Number, Equipment Maintenance Date, Widget Production Date. The Widget Lot Number and Widget Production Date always correspond with each other, but I have this separate list of dates for the Equipment Maintenance Dates that would have occurred on the same Equipment that ran the production. So I would have dates under Equipment Maintenance Date that have no Widget Lot Number to correspond with it. I am trying to figure out how to calculate the amount of time between Widget Production Date and the most recent Equipment Maintenance Date, which otherwise have no way of joining those two data sets (at least so far ).

Thanks!

 

[JumpingCrab]

I have been puzzling over this some time now. I'm not sure if there is a simple way to capture this in a formula. It may require a macro or a userdefined function.