2. Swaziland
Percentage of youth of total population: 23.1%
A sovereign state situated in Africa, Swaziland, which ranks second on our list of countries with the highest youth population, has the lowest life expectancy at birth in the world. Newborn babies, on an average, are expected to live to an age of 52.7 years only. Perhaps some of this can be attributed to the fact that Swaziland has the highest HIV prevalence rate around the globe, causing many people to lose their lives to this horrendous disease.