I write about five thousand words a day, when working on a book, about three thousand a day if I'm writing a short story. I take long periods off between projects, when I read a lot, garden, and think about the next book or stories.
The inspiration to write? Perhaps it's not so much inspiration, as a NEED to write. I get itchy and guilty and dissatisfied when I haven't written for a while. Ideas come to me and need to be written down.