The Top Three, Four, Five Metrics for a News Letter Brand

CNN.com's John Defterios talks to news letter founder and editor-in-chief of the Sydney Morning Herald, David Walliams. Mr Walliams: I think you really have liked the professionalism for a news letter brand down in a way that a lot of other publishers and operators don't quite get right. What are the top canner three, four, five metrics, ps statistics, figures that you really care about, that you're really tracking? And i'd love to jump in with can ove your perspective on when you're thinking about your news letter as a business.