Switzerland METHODOLOGY

For persons aged 15 or older, Switzerland follows the Federal Statistical Office's broad population-with-a-migration-background concept, covering the first and second generation. For ages 0-14, the baseline uses directly observable register variables and includes children born abroad or born in Switzerland without Swiss citizenship. Swiss-born Swiss citizens with two foreign-born parents consequently remain in the native population within this age range.

The model uses the official broad definition from age 15 and a directly observable register classification for children. This keeps the baseline tied to current data for both age ranges.

The total population by individual age and sex comes from STATPOP for 2024. For ages 15 and older, migration-background shares from the Swiss Labour Force Survey are applied to the register population. For ages 0-14, the division is constructed directly from STATPOP using own birthplace and citizenship.

Fertility is differentiated by the mother's citizenship and is applied to populations defined more broadly by migration status. The same age- and sex-specific mortality schedule is used for both populations.

Baseline gross flows for 2015-2024 are classified by country of birth. The principal Swiss migration tables supply immigration and emigration by birthplace, sex and age.

• Below age 15, Swiss-born Swiss citizens with two foreign-born parents remain in the native population under the register-based rule.
• The construction combines the survey-based national migration-status definition from age 15 with register variables below age 15.
• Fertility is differentiated by citizenship, while the population definition from age 15 also includes naturalised persons and Swiss-born descendants.
• Migration flows use own birthplace, the official variable available for cross-border movements.

• Starting migrant share: 39.5%
• Baseline tipping point above 50%: 2038
• Reverse tipping point below 5%: 2088

• Federal Statistical Office: Population by migration status, accessed 26 May 2026.
• Federal Statistical Office: STATPOP population tables, accessed 26 May 2026.
• Federal Statistical Office: Fertility, accessed 26 May 2026.
• Federal Statistical Office: Period life table, accessed 26 May 2026.
• Federal Statistical Office: Immigration by country of birth and emigration by country of birth, accessed 26 May 2026.