Sorry I haven't been updating lately. I might have some time this month to do some of the playing with spreadsheets that I've been wanting to do, especially if the November numbers are reasonably normal. Check the links in the sidebar for the latest updated charts, articles and podcasts.
I did want to take a look at a rare example of a publisher giving precise sales numbers.
http://www.comicbookresources.com/?page=article&id=56841
On WYTCHES #1 : "Image has confirmed that the issue has reached 92,131 copies between its first two printings, with the first printing netting 81,083 in initial retailer orders."
The second print didn't ship until November, so the October numbers should represent the first print numbers only (and the second print should make the November charts).
On the October charts, WYTCHES #1 came in at 67,996, However, it was returnable, and Diamond makes an adjustment for that. The common wisdom is that they reduce the number by 10%, which would put the estimates sales at 75,551. That still leaves a gap of 5532 copies. I'd assume that the number Image reported was the entire print run, including Diamond UK, which isn't included in the North American sales estimates. The common wisdom there is that Diamond UK represents around 10% of the the sales, but that varies wildly by specific book (and down to 0% for some items with licensing or content restrictions), so at about 7% that might seem a bit on the low side, but there were also a number of retailer-specific variant covers for WYTCHES #1 which would definitely lean the numbers more towards North America.
So the numbers would seem to make sense. My initial guess when I read about the print run was that the estimates would come in about 66,000, before I looked at the specific variants which would lean it towards North American sales.
