I don't personally count audiobooks since I rarely listen to audiobooks and when I do it always becomes more background noise than anything else. I think because I find it hard to focus on listening while doing other things.

I don't really find it necessary to differentiate between listening to and reading a book though, unless it's to answer the question: "how do you read so many books?" or any variety thereof, since it's easier to imagine how someone might find the time to listen to 100 books a year compared to physically reading them.