I once argued with someone over a report for an hour.

The report was on a reporting period of 1 month.

The data in that report changes over time for specific period (the one month report references a point in time where data can change as new data is added to reconciled transactions)

I gave up after that hour because I realized no matter how I explained it the concept of a report for a period having changing data because of later reconciliation was impossible for them to understand

I should have asked them the breakfast question.