I have an Atmos clock that's probably 40ish years old, handed down from inlaws, and while I'm sure it needs some service to get it up to snuff, it looses about

I have an Atmos clock that's probably 40ish years old, handed down from inlaws, and while I'm sure it needs some service to get it up to snuff, it looses about a minute a month, give or take.