Busy day, so this is gonna be quick.
Agent Andrew Zack blogged the other day about Bookscan, a service to track and report book sales: The Lie that is Bookscan.
My own agent, Joshua Bilmes, has posted his own thoughts, disagreeing with Zack’s assessment: A Bookscanner Darkly
Personally, I tend to agree with Joshua, and not just because he sells my books. As far as I know, most writers, publishers, and agents know perfectly well that Bookscan represents a percentage of total sales, and that percentage could be anywhere from 70-80% for one author but under 50% for another. Bookscan seems to capture a lower fraction of mine, since I do better with independents.
I don’t think Bookscan ever claimed to report ALL sales. It’s more data than anything else I’ve seen, save from the publisher itself, but it’s definitely not 100% of my sales.
A publisher using Bookscan as the sole criterion for rejecting an author (as described in Zack’s post) is troubling, but I see that as a problem with the publisher, not with Bookscan.
(I do still track and graph my Bookscan numbers every week to fulfil my neurotic validation needs, of course. They don’t tell me actual sales, but they do help me see trends.)