Ah, tangles, there's nothing like a movie to boost sales of the book it's based on. Good to see you're selling well.
A few years ago we went to our local second-hand bookshop just before The Da Vinci Code was released as a movie, 'cos my son wanted to read the book and I couldn't find our copy. Asked at the shop where their copies were and the guy replied, "Oh, we don't have any, all my customers have already read that".
I thought that was just dumb, dumb, dumb. Not only could he have sold a copy to us, but didn't he even consider that he'd be able to sell a few more to people who saw the flick and then wanted to read the book?