Logical Grouping of Helpers

Hello. I would like to keep a “last detected date/time” for each of my 7 cameras.
That data needs to be persistent, so I’m now planning to use 7 separate helpers.
However this might be slightly unruly, so I am looking for any best practices on logical grouping of helpers.

Is there no structure to logically group data items, similar to:

Detected_Date_Group:
  Front_Date:
  Back_Date:
  Side_Date:
   etc.

Looking for standard procedure on this. Seems I could accumulate lots of Helpers over time if they are all stand-alone entities.