Help creating report for pc's that havent been scanned by Inventory in awhile

We have a lot of users that take PC's home and they don't get scanned on the nightly schedule and are out of date for things that need to be deployed. And rather than manually babysitting and kicking off scans during the day, I was trying to create a collection so I could set up a report to email out. I see successful scan and scan status but no way to set it to for anything old that than 30 days or 2 weeks. I can set it to show me scans say after a certain date, but then im manually babysitting a report.

thx