The size and growth of a country’s population are both causes and effects of economic and social developments. The pace of population growth has slowed in all OECD countries.

Demographic trends in OECD countries have implied a sharp increase in the share of the dependent population (i.e. the sum of the elderly and youth population) in the total population, and this increase is expected to continue in the future. These trends have a number of implications for government and private spending on pensions, health-care and education and, more generally, for economic growth and welfare.

Population is unevenly distributed among regions within countries. Differences in climatic and environmental conditions discourage human settlement in some areas and favour concentration of the population around a few urban centres. This pattern is reinforced by higher economic opportunities and wider availability of services stemming from urbanisation itself.

In all OECD countries, populations aged 65 years and over have dramatically increased over the last 30 years, both in size and as a percentage of total population. As elderly people tend to be concentrated in few areas within each country, a small number of regions will have to face a number of specific social and economic challenges and opportunities raised by ageing population.

National views on the appropriate definition of the immigrant population vary from country to country. Despite this, it is possible to provide an internationally comparable picture of the size of the immigrant population, based either on nationality or country-of-birth criteria.

Migration movements include not only entries of persons of foreign nationality, on which public attention tends to be focused, but also include movements of nationals and of emigrants. Net migration summarises the overall effect of these movements. Migration currently represents, in almost all OECD countries, the main source of increases in population.

In most OECD countries, employment rates for immigrants are lower than for native-born persons. However, the situation is more diverse if one disaggregates employment rates by educational attainment.

Immigrant workers are more affected by unemployment in traditional European immigration countries. Conversely, in South Africa, Hungary, the United States and Estonia, the unemployment rate depends less on the place of birth. Some groups, such as young immigrants, women or older immigrants have greater difficulties in finding jobs.