The population’s age structure is influenced by the fertility rate, migration and longer life expectancy.
The number of older persons in Switzerland is increasing. In this ageing society, Swiss nationals are older than foreign nationals. Among
Swiss nationals, there are more persons aged 65 and over than there are young people (0-19 years). The inverse is true of the foreign population: the number of older persons is almost three times less than that of young people.
From 3.7 children per woman at the start of the 20th century, the total fertility rate has fallen to 1.5, which is below the rate required for generation replacement. In order to ensure the renewal of the population, 2.1 children per woman on average is required. The changes to the total fertility rate thus result in a decrease in the share of young people in the population. This phenomenon is called “ageing at the bottom” of the age pyramid.
Life expectancy has doubled in Switzerland: for women since 1878 and for men since 1881. Due to the increasing life expectancy
and the growing share of older persons, the age pyramid is “ageing at the top”.
Migration influences the population's age structure. 20 to 39-year-olds represent the largest group of migrants and contribute to the growth of the generations of people of working age. Three fifths of people arriving in Switzerland and half of those who leave the country are currently in this age category. Due to their high level of mobility, the population of this age category is constantly renewed. Since 2015, the proportion of persons aged 60 and over who emigrate has also been growing. Migration is thus a factor for the rejuvenation of the population.