Ability to see deals that have had activity older than past week


I'm trying to create a deal view where I can see all my deals that have activity past the last week. The purpose is to see which deals we haven't touched on recently.


I can filter "last activity date" by "last week", or "last month", but there is no way to specify anything like "older than X days ago" or "older than X weeks ago". That is really what I want.