rosepetal
I see. Then merely identifying the age of the record wouldn't determine whether or not that record should be removed or kept.
Here's what I might suggest...
1. Add 3 fields to your table. One would be a Date field (call it something such as CreatedDate). The second would be a Yes/No field (call it Removed). The third would be a Date field (call it RemovedDate).
2. In your query which populates the mailings, add the Removed field, and put in criteria "No." That way, any records that have Yes will not get the mailings.
3. Run an Update query to populate all records with the current date, and No in the Removed field.
This will not correct any historical stuff, but it will give you a better handle on things from here on. You can also go through and enter Yes in the Removed field for any records you already know you should not be mailing stuff to anymore.
The virtue in doing things this way is that all records are preserved in your database. So if CustomerA no longer requires a mailing you can remove CustomerA from the mailing list but keep the contact information data...so if CustomerA comes back at some point you still have everything on file.
Tom