Seems that could actually be right, provided that is the number sold in one week. I saw this online regarding what it takes to get into the Times Best Seller list>
"But then Joe asked an editor he trusts, and that editor came back with some pretty convincing data that Joe is absolutely right — that you can, in fact, make it onto the Times top-15 list by selling only 5,000 hardcover copies in a single week."
Don't know how accurate that is, but still seems low to me. I suspect it also depends on your definition of "best seller list" ?? Then there is this >
"Bestsellers are usually separated into
fiction and
non-fiction categories. Different list compilers have created a number of other subcategories. The
New York Times was reported to have started its "Children's Books" section in 2001 just to move the
Harry Potter books out of the No. 1, 2, and 3 positions on their fiction chart, which the then three-book series had monopolized for over a year.
Bestsellers also may be ranked separately for
hardcover and
paperback editions. Typically, a hardcover edition appears first, followed in months or years by the much less expensive paperback version. Hardcover bestseller status may hasten the paperback release of the same, or slow the release, if hardcover sales are brisk enough. Some lists even have a third category,
trade paperback bestsellers.
In the
United Kingdom, a hardcover book could be considered a "bestseller" with sales ranging from 4,000 to 25,000 copies per week, and in
Canada, the
rule of thumb is 5,000 copies sold.
[9] There are many "bestseller lists" that display anywhere from 10 to 150 titles."
(from wiki)
