I have a complete set of Encyclopaedia Britannica bought many years ago at an exorbitant price. They are now worthless except perhaps to a collector. They look nice on the bookshelf and we are reluctant to scrap them but the data in them is now all online and more up to date.
Britannica used to supply an update annual in the same style, covering, etc as the other volumes. This update came at a price of course. With the volumes, indexes, annual editions and one or 2 other volumes I have a total of 42 books. I shudder to think how much they cost and the total value now could be very small indeed.