Is it possible to gerneate reports based on how many mailboxes belonged to an Organizational U (4210219)

Is it possible to gerneate reports based on how many mailboxes belonged to an Organizational Unit on a specific day?

Currently when filter by Organizational Unit it will only report on how many users belong to an organizational unit as of the last sucessful gathering.

There is currently no way to report on how many users belonged to an organizational unit on a given date.

The only workaround is to export a report of the number of mailboxes belonging to which organizational unit on a daily basis via a subscription or manually.