Government Actuary’s Department 2003-based population projections

1 October, 2004

1. The Government Actuary’s Department (GAD) has produced, on 30 September 2004, a revised set of population projections based on the estimated population in mid-2003[1].

2. The projections use previous long-term assumptions about net migration, mortality and fertility. The main change made to previous assumptions is that there is no longer an adjustment for the unexpected results of the 2001 census. Previously a downward adjustment of 27,000 a year had been made for this and this had been included in the heading net migration and other changes making it difficult to identify the full impact of migration.

3. The new projections show the population rising by 6.1 million in the 28 years from 2003 to 2031. Of this increase, 5,181,000 (84.3%) results from migration [2] that is the number of migrants and their offspring.

4. The projections are based on net migration of 130,000 each year. Included in this is an allowance of 15,000 for asylum seekers and their dependants. This assumption only allows for asylum seekers who are granted asylum, humanitarian protection or discretionary leave to remain in the UK. It makes no allowance for those whose asylum claims are not accepted but who do not depart the UK. Currently only about 10% of those who seek asylum are recorded as leaving the UK. Even with the much reduced levels of asylum seekers entering the UK and with the hoped for increase in the numbers of failed asylum seekers removed from the country, 15,000 looks an extraordinarily conservative estimate. A more reasonable number might be 30,000 a year which would put the net migration figure up to 145,000 still well short of the average 158,000 recorded in the last 5 years.

5. A net migration level of 145,000 would cause an increase in population resulting from migration of approximately 5.75 million over 28 years [3] an average increase of over 2 million each decade purely attributable to migration. This makes no allowance for illegal migration.

6. Nearly all of the GADs projected increase in population is expected to occur within England, whose population is expected to rise by just over 6 million by 2031 as shown in the following table:

2003
2031
Increase
Percentage
increase
England
49,856,000
55,881,000
6,025,000
12.1%
Wales
2,938,000
3,153,000
215,000
7.3%
Scotland
5,057,000
4,825,000
-232,000
-4.6%
Northern Ireland
1,703,000
1,840,000
137,000
8.0%
UK
59,554,000
65,700,000
6,146,000
10.3%

7. It may be thought that the very large increase in population resulting from migration is necessary in order to mitigate the effects of an ageing population. In fact it has little impact. If there were no net migration (i.e. the number of immigrants and emigrants were in balance) for every thousand people of working age there would be 710 children or people of pensionable age. Under the GADs assumption of 130,000 net migration a year the ratio would reduce to 677 a reduction of under 5% [4].


Footnotes

[1] Available at http://www.gad.gov.uk/news/documents/2003
based_national_population_projections.pdf
[2] See note on GAD website on effects of migration at http://www.gad.gov.uk/Population/2003/methodology/mignote.htm
[3] Calculated on a pro-rata basis to the GAD’s figures in footnote 2 reference.
[4] Based on GADs principal and natural change population projections. Natural change variant available at http://www.gad.gov.uk/Population/2003/methodology/mignote.htm
Principal population projection available at www.gad.gov.uk/Population/2003/uk/wuk03cc.xls