Why is it that so many 12-month wall calendars for the succeeding year have a page with the last three months of the current year? What do I need that for? I already have a calendar for this year. What might be useful would be one with the first three months of the following year, so that one has a place to write upcoming appointments as they start to creep up, before one puts up, or even acquires, the next year's calendar.
B. and I use the wall calendar for shared appointments, e.g. things we'll do together or those we do individually that impact each other, e.g. if I'll be out for dinner because of a concert. We usually get one with pictures of cats or something equally appealing. I know where the best selection is to be found, and I've just come home with one.
We also keep a page-a-day cartoon calendar, and I've got one of those too. Requirement for these: blank back sides, because we use them for scrap note paper.
I keep my own personal appointments in a bare functional month-at-a-glance calendar. This does have a spread for the next year, in fact spaces for all 12 months, which is very convenient. Along about September, though, it starts getting jammed up, so it's time to buy the next year's. I've done that and transferred all my appointments and commitments, so now I can see when there'll be room to take a couple of trips.