Hello and welcome @Darby_Vannier!
I set up an example table based off your description:
It sounds like creating a filtering view will give you the flexibility you are looking for to create custom views for particular time ranges.
Here is an example of a filter I created to only show Clients who would have active contracts in the month of January (the start date was before January, and the end date was after January):
The summary bar will then show you an automatic sum for currency amount on that view
Hope that helps! Let me know if I can help provide any more information, and if this helped answer your question please mark it as the solution :white_check_mark: .