Definition

The elderly population is the number of inhabitants of a given region aged 65 or older. The population can be either the average annual population or the population at a specific date during the year considered. The average population during a calendar year is generally calculated as the arithmetic mean of the population on 1 January of two consecutive years.

The index of geographic concentration offers a picture of the spatial distribution of the elderly population. It compares the share of population and land area over all regions in a given country and is constructed to account for both within- and between-country differences in the size of all regions. It lies between 0 (no concentration) and 100 (maximum concentration) and is suitable for international comparisons.

The elderly dependency rate is defined as the ratio between the elderly population and the working age (15-64 years) population.

For more statistics on economic, environmental and social issues visit online the OECD Factbook 2010.