Deleting unused lists, but can't tell when they were last used

I am new to a company but have used Constant Contact in the past. I am trying to clean up their over 130 lists and have pared it down to about 60. However, I can't tell what lists have been used recently enough to keep without holding a company-wide Zoom meeting and going through them one by one, or going in to individual contacts and seeing what they have opened recently. With over 50 employees and 25,000 contacts, that is too much of a time burden. Is there a way to view when lists were last used? Thank you for your help!