Population and Labour Force Projections 2017 - 2051

The following chapter contains the fertility assumptions agreed by the Expert Group and the issues considered in reaching their decision.  Based on their analysis the Expert Group considered that the most likely out-turn for overall average fertility over the projection period, as measured by the Total Fertility Rate (TFR), would be in the range 1.8 to 1.6.  

Two variants were chosen: a high variant (F1) which assumes that TFR will remain at the 2016 level of 1.8 for the lifetime of the projections and a low variant (F2) which assumes that TFR will decrease to 1.6 by 2031 and remain constant thereafter.

The main items deliberated on prior to reaching agreement are discussed in the subsequent sections, including:

- Historical and recent trends in births
- Age specific fertility rates
- Number of women of child bearing age
- Average age of first time mothers
- Comparisons with other European countries

The number of births each year in Ireland has varied over the past 50 or so years, rising from just under 60,000 in 1961 to a peak of over 74,000 in 1980.  This was followed by another period of decline, with just 48,250 being recorded in 1994. The number of births peaked again in 2009 reaching 75,550.  Births have declined steadily since 2009, with fewer than 65,000 births recorded in 2016.

The main factors which impact on the number of births are the number of women of child bearing age (15 - 49 years) and their fertility levels. The total fertility rate (TFR) was as high as 4.03 in 1965 but it has fallen steadily thereafter. The age specific fertility rates (ASFR) also show a general decline with a rate of 228.7 for women aged 25 - 29 in 1970 down to 75.1 in 2016. Similar trends can be observed in all age groups, with those aged 30 - 34 falling from 201.9 to 122.5 in 2016 while the 20 - 24 age group fell to 38.6 (from 145.5 in 1970). See table 4.1.

One exception to the secular decline is when the fertility rate rose from 1.85 in 1995 to 2.1 in 2008. This may have been caused by the tempo effect, which is the effect of women in their twenties delaying having children until their thirties or early forties. This causes a temporary decline in the fertility rates and then a recovery as the delayed births occur.  Indeed the ASFR for those aged 30 - 34 rose from 123.5 in 1995 to 140.1 in 2008, while the fertility rate for those aged 35 - 39 years rose from 60.3 to 100.6 in the same year.  However the rates subsequently resumed their downward trend.

Not only are the age specific fertility levels declining, but the number of women in the younger age groups is also falling.  For example, the number of women aged 20 - 29 has been in decline in recent years, falling from 383,000 in 2009 to nearly 287,000 in 2016 (-25.1%), while the number of women aged 30 - 39 has remained static at around 385,000 since 2012.  This can be compared to the period between 1991 and 2008 when the number of women aged 20 - 29 grew by almost 135,000 (52.7%) and the number of women aged 30 - 39 increased by 108,500 (44.3%).  The combination of declining fertility rates allied with a decrease in the number of women of child bearing age has resulted in the fertility rate falling from 2.10 in 2010 to 1.82 in 2016 or a decline of 13.3%.  See table 4.2 and fig 4.2.

The Expert Group also noted that the age at which women are deciding to have their first child is rising year on year and that this would impact on future fertility rates if the trend were to continue. There has been an increasing trend towards later births, with the average age of first-time mothers rising by 7.5 years for those inside marriage between 1975 and 2015 and by 6.3 years for those outside marriage over the same period (21.8 to 28.1 years).  See fig 4.3.

The high fertility assumption F1 assumes the total fertility rate will remain at the level observed in 2016 of 1.8 for the lifetime of the projections up to 2051.  This assumption sees fertility levels remaining below the theoretical replacement level (2.1) but still close to the top of the EU fertility table.  See Fig 4.4.

The low fertility assumption F2 assumes the total fertility rate will decrease from 1.8 to 1.6 by 2031 and then stabilise at this level until the end of the projection period in 2051. The Group considered that this assumption would allow Ireland to remain in line with the 2016 EU average fertility rate while still allowing a decrease to take place from the current level.

It is assumed that the rate of decline in fertility under F2 will be uniform across all age groups. While there has been some variation in the way the fertility of women in different age groups has evolved in recent years, adjusting age specific rates within the agreed overall TFR has little impact on the total number of births. Furthermore, given that the principal purpose of the fertility assumptions are to generate projected annual number of births to feed the projection model, the distribution of these births according to the age of the mothers is considered to be of secondary importance. The assumed age-specific and derived total fertility rates under assumption F2 are given in Table 4.3.

While this report contains a number of summary tables, detailed results of the population projections from 2017 to 2051 are available on the CSO Statbank here.