This table contains invoices, with paid amounts and outstanding balances.

This is not a simple fact table.

A history of rows is kept for every invoice over time.

Each time a row changes, including outstanding amounts aging into the next aging bucket, the old row is end dated with the previous days’ date

The new row has a start date of the current date.

To retrieve the current records, filter on Current Flag = Y.

Key point: On a given day, an aged trail balance report can be found by returning all current versions of invoice rows.