The French population reached 68.6 million on the 1er January 2025, an increase of 0.25% compared to 2024. But the population of France may not grow for much longer, according to the latest estimates from the National Institute of Demographic Studies (INED). According to its predictions, the natural balance, that is, the difference between births and deaths, will become negative as early as 2027. Gilles Pison, demographer, professor emeritus at the National Museum of Natural History (MNHN) and advisor to the INED management, reviews these forecasts with us.
Sciences et Avenir: According to your projections, the number of deaths should exceed the number of births by 2027. Were you surprised by this very near horizon?
Gilles Pison: This result is arrived at by three assumptions. Indeed, this projection is based on the assumption that the trends of previous years will continue. First, the decline in the number of births began in 2010. Births today correspond to a fertility rate of 1.62 children on average per woman and it is assumed that fertility will remain stable. It is also assumed that net migration, the difference between entries and exits in France, estimated at 152,000 for 2024, will continue. And finally, it is assumed that trends in life expectancy at birth – which is always increasing – will continue in the following years. The excess of births over deaths, which decreases from year to year, would become zero in 2027 and deaths would then be more numerous.
"The excess of deaths over births should be offset by net migration until 2040."
Despite this reversal, the population would continue to grow, reaching a peak of 70 million in the 2040s, before gradually declining to 68 million in 2070. How is this possible?
After 2027, the excess of deaths over births should be offset by net migration until 2040. But beyond that, the number of deaths will be too high for immigration to compensate for this loss. This phenomenon stems from the arrival at advanced ages of people born during the baby boom, between 1946 and 1973. All of these people are between 50 and 80 years old today. In the coming years, they will continue to age and retire. And over the next 30 years, we will witness the death of baby boomers. Since there are so many of them, France will not escape an increase in the number of deaths. However, if net migration remains as it is today, it will not be able to offset these many deaths.
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Before returning to 68 million inhabitants in 2070, the same figure as today, we should reach a peak of 70 million inhabitants in the 2040s. Under what conditions could we reach this maximum?
All of this is based on the assumption that fertility will remain at the same rate as in 2024. But it can also decline or increase again. Indeed, when we examine the variations in births since the baby boom, we observe periods of decline, like today's, which began in 2010, but also periods of increase, also in the 1980s and early 1990s. At the low point of 1993-1994, women had an average of 1.68 children. Then, in the second half of the 1990s and in the 2000s, this figure started to rise again. The question today is: is the downward trend part of the fluctuations we have observed since the end of the baby boom, with a possible rise later, as happened 30 years ago? Or will the demographic regime actually decline, with women giving birth to fewer children than their mother's or grandmother's generation?
"In 50 years, the age of having a first child has increased from 24 to 29."
Do we already have an idea of how the number of children per woman will change in the years to come?
Beyond the fertility rate, we use another indicator called the " final descent »This is an assessment carried out when women reached the age of 50. It appears that women born in 1974 – who therefore turned 50 last year – have had 2.02 children each. Those born in 1984 – who will be 40 in 2024 – already have 1.98 children on average each. However, they will probably have a few more children. So the number of children will be slightly higher than 2. Those born in 1994 – aged 30 in 2024 – already have 0.86 children on average each. It is difficult to know how many children all these women will have by the time they turn 50. But what we can already say is that until now, in France, women have had as many children as their mother's generation, but later in life. In 50 years, the age at which women have their first child has increased from 24 to 29. The question remains how many children these women will have by the time they reach 50.
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