You can't do exactly what you ask without writing some Applescript. However, you may not need to do that, if you are willing to assume that the present is one endpoint of the reporting interval, and the other endpoint is in the recent past.
I have a perspective that shows me items completed today. Here are the view bar settings:
I have the Completed Today group open in this perspective, and the others closed. If I wanted to look at more than one day, I would probably change the sort to Completed instead of Project.
You've got a couple of options at this point. You could print or export the contents of that group on a daily basis as documentation for the status report. Another option would be to print or export the contents of as many groups as you need to open to cover the time in question (here you would probably want to sort by date completed as I suggested, and do not group, giving you a chronological list from most recent to least recent).
If you are comfortable with Applescript, or willing to learn, you could write a script that traverses the database looking for completed actions between the dates you specify. If you do that, please post the script to the OmniFocus extras forum.