The total fertility rate is below the estimated replacement level – the number of children per woman needed to keep the total population constant in the long term – of about 2.1 in developed countries in 2024, in all OECD countries except Israel. Fertility rates fell sharply in the second half of the 20th century and after a small bounce in the 2000s they have resumed with their downward trend. Over the last 20 years, fertility rates decreased in all except 10 OECD countries, often in Central and Eastern Europe, where they had reached very low levels. Fertility rates have a profound implication for pension systems because they, along with life expectancy, are the drivers of substantial shifts in demographic structures. Since 1960, differences in fertility rates across countries have been reduced.
Pensions at a Glance 2025
OECD countries have been experiencing a long-term decline in the Total Fertility Rate (TFR) since the 1960s. The decline stopped temporarily during the 2000s but resumed after the great financial crisis of 2007‑08. Fertility rates currently average 1.46 across OECD countries, well below the level that ensures population replacement (Table 6.1). Among OECD countries, the TFR is highest in Israel with 2.8 children per woman followed by Mexico at 1.9 and New Zealand at 1.7. It is by far the lowest in Korea at only 0.7 children per woman. Chile (1.1) and Italy, Japan, Lithuania and Spain (all 1.2 children per woman) also have very low rates.
The fall in fertility rates reflect changes in lifestyle preferences, in family formation, and in constraints of everyday living, such as those driven by labour market insecurity, difficulties in finding suitable housing and affordable childcare. Recent years have also been marked by a change in attitudes towards parenthood. Both young men and women increasingly find meaning in life outside of parenthood, and there is a broad movement towards an increased acceptance of not having children.
At the same time, the normative demands on what it means to be a “good” parent have grown in importance, and the changing balance in costs and benefits of having a child – both financial and non-financial – drives choices to have fewer, if any, children today than in the past. The childbearing patterns of unmarried men and women have also changed. For example, half or more of births now occur outside of marriage in France, Iceland, Norway and Sweden. The average proportion of births outside marriage in OECD countries is now one‑third of the total.
Over the last 50 years, there has been a steady convergence in fertility rates across OECD countries. In the early 1960s, Colombia, Costa Rica, Korea, Mexico and Türkiye had rates around twice the OECD average, with Hungary and Latvia not much over half. The standard deviation across countries declined from 1.31 in 1964 to 0.29 in 2024.
Since 2004, the fertility rates have slightly increased in 10 out of 38 countries while the average has decreased by 0.2. The increases from a very low level have been the strongest in a few countries, including Czechia (+0.23), Hungary (+0.20), the Slovak Republic (+0.31) and Slovenia (+0.33). The largest declines, from relatively high levels, have been observed in Colombia (‑0.74), Costa Rica (‑0.70), Mexico (‑0.65) and Türkiye (‑0.58).
While the average fertility rate will be 1.53 across OECD countries by 2064 according to the median forecast of the United Nations Population Prospects, forecast uncertainty is considerable, with the 20th percentile of probabilistic projections for the OECD average at only 1.17 and the 80th percentile close to reproduction at 1.88 (Figure 6.1). Past projections have systematically overestimated TFRs. Past estimates of 2025 TFRs have been corrected downward in almost every new edition: while the 1994 edition still foresaw an average TFR of 2.01 in 2025 across OECD countries, by the 2024 edition the estimate had decreased to 1.46 (Chapter 1).
As a result, the old-age to working-age ratio will increase sharply placing additional burdens on the working-age population to finance pay-as-you-go pensions and healthcare for older people.
Among the other major economies, Indonesia, Saudi Arabia and South Africa all currently have fertility rates above the replacement level of 2.1, with India just below. However, the downward trend is expected to continue in these countries, with fertility rates going below the natural replacement rate by 2030. By contrast, the trough has now been reached in China with levels projected to increase over the next 40 years.
Definition and measurement
The total fertility rate is the number of children that would be born to each woman if she were to live to the end of her child-bearing years and if the likelihood of her giving birth to children at each age was the currently prevailing age‑specific fertility rate. It is generally computed by summing up the age‑specific fertility rates defined over a five‑year interval. A total fertility rate of 2.1 children per women – the replacement level – broadly ensures a stable population size, on the assumptions of no migration flows and unchanged mortality rates.
Further reading
OECD (2024), Society at a Glance 2024: OECD Social Indicators, OECD Publishing, Paris, https://doi.org/10.1787/918d8db3‑en.
Note: The data refers to 5‑year periods whose endpoint is indicated in the first row of the table.
Source: United Nations, Department of Economic and Social Affairs, (2024). World Population Prospects 2024, Online Edition (for future periods: medium-variant forecast).
Low, medium and high variant projections for 2064
Note: Low, medium and high variant projections correspond to the 20%, 50% and 80% percentiles of probabilistic projections, respectively.
Source: United Nations, Department of Economic and Social Affairs (2024). Probabilistic Population Projections based on the World Population Prospects 2024: http://population.un.org/wpp/.