shrug https://www.economist.com/blogs/economist-explains/2013/08/economist-explains-18 https://www.economist.com/blogs/economist-explains/2013/08/e... These g

shrug https://www.economist.com/blogs/economist-explains/2013/08/economist-explains-18 https://www.economist.com/blogs/economist-explains/2013/08/e... These guys tried to answer that question. Still, it seems to me that even they didn't touch on any good answers. shrug