In my ~2years of pipe smoking I think I've only finished, maybe, one tin. This is more of a function of a deeply rooted TAD disorder and infrequent smoking (maybe twice a week). I have 44 different blends now which I hop between haphazardly. When I've decided I really like a blend more than its neighbours I stock up on some to cellar.
About a bowl a day -- some days two, others none. I'd guess a tin a month, but from a fairly large rotation, five or six blends, samples, and a few non-rotation blends. An aro now and then. I'm not above letting a pipe go out and taking it up the next day. I sometimes let a bowl of rubbed out leaf sit in a bowl drying for a few days before I finish it completely. Very low key here.
Old joke: I don't smoke any more. I don't smoke any less either.