You are right... But you also have to keep in mind populations. China and India are going to skew the over all statistics to the left. That draws the world average down, because you have 2 populations accounting for nearly 3/7ths of the over all population (With China around 1.4b and India being around 1.2b). European nations account for far less. The whole of Europe + the US accounts for 1 billion. People's Republic of China is right at 5'7", which "China" listed at 5'8", but I presume by China, it means The Republic of China... or Taiwan as we call it, which is a lot less populous. A lot of the South American nations don't report in for males on the list, but extrapolating from the female scores listed... a lot of them are going to have smaller than average males too, pulling the world population down.