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As can be vividly shown from the pie charts of Yemen and Italy, we can see them divided into three sections, showing relative proportions of populations for different age groups in 2000 and projections for 2050.
Yemen, whose food supply can’t be self-sufficient and mainly relies on imports, is one of the most underdeveloped countries in economy. In the year 2000, people aged from 0 to 14 accounted for 50.1%, 46.3% in the 15~59 year-old range, and 3.6% over 60 years old. Subsequently, the population of the former group is predicted to be increased by 13.1%, the second group a 11% rise, while the latter group over 60 is conjectured to go up to just a small extent by 2.1%. Quite possibly, the sluggish economy can be the likely reason for the less obvious gap in 2000 and projections for 2050 than that of Italy. On the other hand, Italy, as the 8th economic entity in the world, ranked among the world top in terms of living standards. The population of the first group is presumed to decline about 3% through the control of birthrate by the government. Therefore, the second group is accordingly reckoned to a drop of 15%. And the population over 60 is speculated to a sharp rise of nearly 20%.
In conclusion, the disparity of population groups between Yemen and Italy is immensely attributed to the national policy, economic strength and the perfection of healthcare system.