List of countries by past and estimated future population


Introduction

All the figures shown here have been sourced from the International Data Base Division of the United States Census Bureau. Every individual value has been rounded to the nearest thousand, to assure data coherence, particularly when adding up 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 GDP, which are much more sensitive to political and/or economic crises. This means that demographic estimates for the next five years can be more accurate than the projected evolution of GDP over the same time period.
However, no projected population figures can be considered exact. As the IDB states, "figures beyond the years 2020-2025 should be taken with caution", as the "census way towards those years has yet to be paved". Thus projections can be said to be looking through a kind of "cloudy glass" or a "misty window": realistically, the projections are "guesstimates".
To make things complicated, not all countries carry out censuses regularly, especially some of the poorer, faster-growing sub-Saharan African nations. As is well known from the statistics, the population of many sub-Saharan nations, as well as other nations like Algeria, Bangladesh, Egypt and Pakistan, with their low family planning, are growing much faster than in the aging European nations or Japan. In general, although population growth in the former countries may slow in the future, it is unlikely that it will have stabilized 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 per year, despite its government's efforts to stabilize it through its one child per couple policy.
On the other hand, some other countries, like the small Asian state of Bhutan, have only recently had a thorough census for the first time: In Bhutan's case in particular, before its national 2005 population survey, the IDB estimated its population at over 2 million; this was drastically reduced when the new census results were finally included in its database.
Besides, the IDB usually takes some time before including new data, as happened in the case of Indonesia. That country was reported by the IDB to have an inflated population of some 242 million by mid-2005, because it had not still processed the final results of the 2000 Indonesian census. There was a similar discrepancy with the relatively recent Ethiopian 2007 census, which gave a preliminary result of "only" 73,918,505 inhabitants.
The largest absolute potential discrepancies are naturally related to the most populous nations. However, smaller states, such as Tuvalu, can have large relative discrepancies. For instance, the 2002 census in that Oceanian island, which gave a final population of 9,561 shows that IDB estimates can be significantly off.

Preliminary notes

The national 1 July, mid-year population estimates supplied in these tables are given in thousands.
The table columns can be sorted by clicking on their respective heading.
The retrospective figures use the present-day names and world political division: for example, the table gives data for each of the 15 republics of the former Soviet Union, as if they had already been independent in 1950. The opposite is the case for Germany, which had been divided since the end of the Second World War but was reunified on October 3, 1990.
Other issues concerning some countries or territories are as follows:
Finally, the Eastern and Western Europe subtotals follow the former Cold War's Iron Curtain division of Europe.

Formulas used to calculate demographic growth

To the right of each year column, a percentage figure is shown, which gives the average annual growth for the previous five-year period. Thus, the figures after the 1960 column show the percentage annual growth for the 1955-60 period; the figures after the 1980 column calculate the same value for 1975-80; and so on.
The formulas used for the annual growth rates are the standard ones, used both by the United Nations Statistics Division and by National Census Offices worldwide. They are compound growth rates, and have the general form:

where and stand for the initial and final population, respectively, within a stated time period. Similarly and are the dates of the initial and final years.
In the calculations shown here, all the periods are of five years, and so yi + 5 = yf, so the formula simplifies to
.

Estimates between the years 1950 and 1980 (in thousands)

Estimates between the years 1985 and 2015 (in thousands)

Estimates between the years 2020 and 2050 (in thousands)

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