This is a bit random, but do publishers like Penguin move a lot of classics each year? Middlemarch’s rank in the Amazon USA list would seem to indicate it sells around ten copies a day. Does that seem reasonable? I thought it seemed a bit low, but my opinion is truly random. There are >12 different paperback editions, so that would seem to argue for popularity…
I don’t know the answer to this, but I imagine one of the factors at play is that most used book retailers are flooded with copies of popular classics. If I didn’t already own Middlemarch and wanted a copy, I’d head to my local used bookstore and get a copy for ~$3/4. The fact that the authors for classics are no longer alive means I would always go for used copies over new.
So the number of copies that are being purchased and read includes more than just how many copies Amazon is selling new. Also, I wonder how this metric is arrived at. Because if ~10 copies of Middlemarch sold per day is just reflective of one of the many, many editions of the book available on Amazon, then I could see it. But if it’s all editions of Middlemarch, then that does seem a little low. We’re talking about the number one book retailer in the world.