CBS figures show 44,000 Dutch birthdays on 30 September as longevity rises

September birth peaks across Dutch municipalities

On 30 September, more than 44,000 people across the Netherlands celebrate their birthday, reflecting a seasonal concentration of births occurring nine months after the late December holiday period. Data released on Wednesday by the national statistics office CBS shows that daily birth counts differ markedly from town to town. In Amsterdam, 1,620 residents celebrate on 30 September compared to a daily average of 1,577, while the city's highest single-day count occurs on 24 September with 1,722 birthdays. Utrecht records 863 birthdays on 30 September against a daily average of 787, with its yearly peak of 889 falling on 7 May. In smaller municipalities, Leiden counts 289 birthdays on 30 September, Oosterhout counts 175, Kampen 159, Wijchen 107, Vught 106, and Etten-Leur 104.

Urban-rural divides in age distribution

CBS figures as of 1 January show distinct divides in the largest single-year age cohorts across different municipalities. In student-oriented and university cities, the largest demographic segments consist of young adults. Amsterdam's single largest cohort is 29-year-olds, numbering 21,925 residents, while Utrecht's peak cohort is 28-year-olds with 9,027 people. Leiden's largest group is 23-year-olds with 3,497 residents, and Kampen's peak is 18-year-olds with 801 individuals. By contrast, suburban and regional towns feature peak cohorts entering or approaching retirement. In Vught, the largest group is 63-year-olds (523 residents), in Oosterhout 61-year-olds (895 residents), in Wijchen 60-year-olds (713 residents), and in Etten-Leur 56-year-olds (664 residents).

Longevity gains and demographic aging

Estimates from public health agency RIVM indicate that life expectancy for newborns has risen across every surveyed area since the turn of the century. For children born between 2021 and 2024, projected average lifespans reach 82 years and six months in Wijchen, up from 78 years and seven months for the 1999 to 2002 cohort. Newborn life expectancy stands at 82 years and two months in Kampen, 81 years and 11 months in both Oosterhout and Etten-Leur, 81 years and two months in Utrecht, 81 years and one month in Amsterdam, 81 years in Vught, and 80 years and ten months in Leiden. At the upper end of the age scale, Amsterdam counted 150 residents aged 99 or older at the start of the year, with its oldest resident aged 105. Utrecht registered 51 residents aged 99 and older, Leiden had 32, Kampen ten, Vught and Oosterhout nine each, Etten-Leur six, and Wijchen five.

Shifting proportions of older and younger residents

Nationwide, more than 20% of residents are now aged 65 or older, though local rates vary across municipalities. Older residents account for 24% of the population in Wijchen, Vught, and Oosterhout, and 23% in Etten-Leur, with all four recording steady increases since 2015 or 2017. In Kampen, the 65-and-over cohort grew from 16% in 2015 to 19%. Major university cities remain younger than the national average, with Utrecht at 11%, Amsterdam at 14%, and Leiden at 17%. Concurrently, declining national birth rates have reduced the proportion of children and teenagers. In Wijchen, the share of youth dropped from 24% in 2015 to 20%, while Kampen fell from 27% in 2017 to 24%, Utrecht from 23% in 2015 to 21%, Amsterdam from 20% to 18%, and Etten-Leur from 23% in 2018 to 21%. Fewer than 100 Dutch municipalities, including Vught and Oosterhout, have avoided noticeable drops in youth population shares.