Playing With Numbers Again 10th January 2011.

I’ve been playing around with numbers again, this time trying to get my head around the sales ranking system Amazon uses to rank both its print and Kindle books in order to intelligently answer questions from our authors. (Ed – Huh? Answers? Nobody told me he’d answer questions!)

In no way am I trying to be critical of Amazon but it really is a beast to get your head around and I’m greatly indebted to an article by Morris Rosenthal at Foner Books for the analysis he has put together and who gave his kind permission to quote it here.

The sheer numbers of titles both listed and shipped by Amazon in both print and electronic from is absolutely staggering. Although, clearly, not all books listed are still in print so are no longer current, they have listed a staggering total of several million books over the years. The total number of Kindle books doesn’t yet approach this, but must by now be close to a million.
So how does the ranking work? How many sales do you need to get into the top 10,000 best sellers (this is of course overall and not by category)? How many do you need to get into the top 100,000 or even the top 1,000,000?

The answer is in fact, surprisingly few.

In print terms, if you sell a book a year you’ll probably be in the top 2,000,000. If you sell a copy every ten weeks you’ll make it into the top 1,000,000. 1 copy a week, the top 500,000 and 10 copies a week the top 100,000. You’ve probably got to be selling 200 copies a week to make the top 1,000.

In e-books the pattern is very similar, 1 book every 10 weeks gets you into the top 200,000, 2 copies a week the top 100,000 and probably around 50 copies a week to break the top 10,000, 450 a week to make the top 1,000.

The actual rankings are recalculated hourly and are hugely volatile; you can gain or lose 1,000 or 10,000 places without even selling a single copy. It’s exciting to see your book creeping or even jumping up the rankings and then in turn devastating when it suddenly drops again and as an author you get the impression your book is no longer popular. This isn’t true of course; it’s simply the vagaries of statistics when your book is one among such a huge swarm.

The UK rankings are of course a mini version of the US ones, especially since the Kindle hasn’t been out as long or, as yet, so popular over here. It is becoming so though.

It is interesting to note with the best sellers, where both versions are available, the average Kindle Sales ranking is pretty much equivalent to the average print ranking.

For myself, one of my paperback books is currently languishing below 2,000,000 – so I can only hope someone buys a copy real soon... Just the one... Please... Somebody...