Evolution of the population

The size and growth of a country’s population are both causes and effects of economic and social developments. The natural increase in population (births minus deaths) has slowed in all OECD countries, resulting in a rise in the average age of populations. In several countries, falling rates of natural increase have been partly offset by immigration from outside the OECD area.

Definition

The tables refer to the resident population. For countries such as France, the United Kingdom and the United States which have overseas colonies, protectorates or other territorial possessions, their populations are generally excluded. For full details, see Sources below.

Growth rates are the annual changes in the population and are the result of births, deaths and net migration during the year.

The total fertility rate is the total number of children that would be born to each woman if she were to live to the end of her child-bearing years and give birth to children in that period in agreement with the prevailing age-specific fertility rates.

Comparability

For most OECD countries, population data are based on regular, ten-yearly censuses, with estimates for intercensal years being derived from administrative data such as population registers, notified births and deaths and migration records. In several European countries, population estimates are based entirely on administrative records. In general, the population data for OECD countries are reliable, although, for some countries, there are breaks in the series as indicated by vertical lines in the tables.

Note that for some countries the population figures shown here are not those used for calculating GDP and other economic statistics on a "per head” basis. There are several reasons for this, but the differences between the two data sets are normally small.