I actually haven't had a cigarette in over 2 weeks, simply because I haven't felt the urge to have one. I may not smoke another cigarette for another week, I may not smoke one for another month or two, I may never smoke one again, who knows? I am not addicted.
Aside from that, I've smoked since I was 11 and I'd probably average out to 3 or 4 cigarettes a day, including the gaps when I don't smoke. I seem to smoke more when on tour, except for the UK since you can't smoke in the venues here anymore.
I used to smoke a lot more. When I was 14-16 I probably smoked 7 or 8 a day. But that was in high school and there was nothing else to do.