List of countries by past and future population

The figures shown here have been entirely taken (and processed) from the International Data Base (IDB) Division of the United States Census Bureau. Every individual value has been automatically rounded to the nearest thousand, to assure data coherence, particularly when adding up (sub)totals. Although data from specific statistical offices may be more accurate, the information provided here has the advantage of being homogeneous.

Population estimates, as long as they are based on recent censuses, can be more easily projected into the near future than many macroeconomic indicators, such as GDPs, which are much more sensitive to political and/or economic crises. This means that it is more accurate to make demographic estimates for the next five (or even ten) years than trying to calculate the probable evolution of a GDP through the same time period (besides, in this latter case, deflating has to be taken into account to compensate or make up for the distortion caused by inflation).

However, no projected population figures can be considered exact. In the IDB's particular case, figures beyond the years 2020-2025 should be taken with caution, as the census way towards those years has yet to be paved. Thus, from a present-day point of view, it is as if a demographer was looking through a kind of cloudy glass or misty window, and more or less precise "guesstimates" are the only realistic present-day available possibilities.

To make things more complicated, not all countries carry out censuses on a regular basis, especially some of the poorer, faster-growing sub-Saharan African nations (whose evolution may be more interesting, from a demographer's point of view, than the stagnated populations of countries like Germany or Italy). As it is widely known in the world of demographics (from historical empirical data), countries like those (along with other nations like Algeria, Bangladesh, Egypt and Pakistan) -with their low family planning- tend to grow much faster than the aging European nations or Japan. In general, although the former countries may slow down their respective demographic growths rates in the decades to come, it is unlikely that they will stabilize their respective populations by 2050, as predicted by the IDB data in some cases; they may also stay near the relatively high average level of 1.5% increase per year. Something similar can be said about China, whose population is still growing at an absolute rate of some 10 million additional inhabitants per year, despite its government’s efforts to stabilize it, through its one child per couple policy.

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