Interesting, but I would of assumed most countries in the ME to have such a high young % due to the ongoing wars/invasions/attacks in that region. It'd be interesting to correlate this with the female % of population, may be similar.
A lot of demographers would say that the causation goes the other way around from what you said, in other words that countries with young populations tend to get involved in more wars and more domestic unrest.
Yep -- all you need to get a good war going is an excess of young men and a border. For a domestic conflict you can skip the second part.
Or you can look at it from a purely economic standpoint: if your military-aged men are mostly finding gainful employment and you want to raise an army you need to either conscript or pay competitive wages. Either way you're damaging your economy. If you have far more people that age then prospective jobs it's way cheaper to convince some of them to put on a uniform.
I find North and South Korea to be a fascinating demonstration of the effectiveness of governmental policy to shape people's quality of life, for better or worse.
I am sure the correlates with the flattening of the world population, to the extent that wars and mismanagement of resources are mitigated world wide the birth rates rise and then flatten out. One of those times where you wish you had statistics from 0 to present.
I'm guessing that's how the data are actually gathered for whatever reason. The UN World Population Prospectus has various breakdowns here, and they group people in 5-year groups, so there's a break at 14 and a break at 19. I'm guessing that's where this chart came from.
If I had to make an educated guess, I'd say it's probably done this way to make data more comparable between countries for whatever reason. I'm not exactly sure why that would be necessary, but generally when you see something weird like this, it's because something changes a lot from culture to culture, so they use wider buckets to capture everyone who is reasonably comparable. Maybe it's some combination of when different cultures start counting your age and a lack of good birth records in poorer areas, and they figure people can more or less estimate which 5 year block you're in. Another possibility is that the older data sets were collected using some form that had you blocked off in 5 year blocks for whatever reason, and they can't change it now without invalidating the comparability of the data sets.
EDIT: If anyone's interested, I found this manual [1] on estimating population age and sex where they go into detail about the assumptions in the five-year age group method. Doesn't really explain why this is desirable, though - I think it might have something to do with how census data are collected in different countries.
I think it could be because of education programs, where available of course. I'd guess most of the country enforcing mandatory schooling do it for people below 14~16 years old. For instance France is 16, India is 14, Japan is 15. I'd wager in these countries there is more resources spent and more reliability in tracking the children below the minimum schooling age.
Although it is interesting, I think that the data should be normalized for life expectancy. A country with a lower life expectancy will necessarily have a younger population. So instead of 14 years old, it would make sense to show the age of the (e.g.) first percentile of the population.
> A country with a lower life expectancy will necessarily have a younger population.
This is not necessarily true. Generally the number for "life expectancy" that is quoted is life expectancy at birth, which is roughly the average age of people at their death. In a lot of poorer countries, this number ends up being driven by infant mortality (to see why, consider a country where, if you survive infancy, you live to be 100 years old, but 50% of all infants die - the "life expectancy at birth" of such a country would be about 50).
Generally, I think it's understood that the "youth" of a population is a sort of measure of adult life expectancy. Though I suppose it can also be a measure of the birth rate (weighted by infant mortality) across countries. I think the two factors end up being fairly intimately tied to one another (likely by a third factor, wealth), so it's not absurd to conflate the two.
