How Many Readers?

I've directly sold around 1 million new copies. But my books have been read far more broadly than that. Whilst authors don't earn anything from the sale of second hand copies of their books, around half as many people who have bought them new have bought second hand copies. Most people who've bought one or more of my books (new or second hand) report they have loaned them to between 2-10 people. Around a quarter of my readers have read more than one of my books and many have several, some have all 10.  Around 10-20 times the number of people who have bought a new or second hand copy or loaned a copy from a friend, have borrowed one or more from a library. Based on those who only borrowed 1 of my 10 published books (some libraries have a copy of 1, 2, 4, sometimes the whole 10 and I have heard waiting lists to borrow a library copy) this would bring the conservative estimated number of people who have read at least one of my books to around 40-200 million readers.