The link you gave confirms what I've said here. > The quote is either wrong or outdated. In the second edition, it's on page 521: "Industry average experience

The link you gave confirms what I've said here. > The quote is either wrong or outdated. In the second edition, it's on page 521: "Industry average experience is about 1 - 25 errors per 1000 lines of code for delivered software. The software has usually been developed using a hodgepodge of techniques. 1-25 is not a single number - it is a range.