Demography and the UK

Demographic consequences of international migration to the UK and other developed countries

Earlier work analysed the issue of population ageing and evaluated critically the utility of the concept of ‘replacement migration’ as a possible solution (see Working Papers no 3, 4, 5) . More recent work, which continues, investigates the demographic and workforce consequences of international migration to and from the UK and other Western countries in the post-war period and projected into the future. The UK research was funded initially by the Nuffield Foundation and aspects of this research have since been continued in collaboration with Dr Sylvie Dubuc through an ESRC UPTAP award (see below). This research has a number of aims. First to update earlier estimates by Martin Smith (former Research Officer) of ethnic differentials in fertility, and to produce for the first time estimates of religious differences in fertility.  Following that, produce a set of population projections of the likely size and composition of the immigrant and minority populations in the UK in the 21st century, including religious categories; and to evaluate the past, present and future effect upon the workforce.

A brief description of the initial project can be found in Working Paper no 12. The estimation of fertility, mortality and migration levels and trends is presented in Paper 13 and 28, reviews of the demographic consequences of migration in various European countries was published in 2003 (Working Paper no.18) and 2006 (Paper no. 33). In the last paper it was suggested that the substantial changes in the ethnic composition of European countries arising from immigration should be regarded as a 'third demographic transition'. A later paper (Working Paper no 54) discussed the prospects for such transformations becoming widespread in the developing world, as well as in Europe and the US, as their economies progress. It concluded that current and projected high levels of ethnic diversity arising from post-war immigration will remain confined for the most part to the current developed world except for some smaller countries.

A somewhat different approach has been followed with colleagues from the Vienna Institute of Demography. A probabilistic projection to 2100 of the UK (the first to be produced) with four broad ethnic categories, has been presented (Paper 29) and an 8-category version is in preparation. OXPOP has also collaborated with Sergei Scherbov and with Dalkhat Ediev in the development of Ediev’s original reformulation of population reproduction.  New indicators of reproduction incorporate migration and the fertility of migrants, unlike conventional measures such as total fertility and net reproduction (

A more conventional but more detailed cohort-component projection of the ethnic composition of the UK to 2056 has been published (Population and Development Review 36. 3). An unedited version can be found at Working Paper no 55.  This made use, among other data,  of estimates of fertility  according to ethnic group, using the own-child method , published in ‘Population Studies’; see also Working Paper 53. Projections are provided on four different assumptions on the level of international migration, of twelve ethnic groups in the UK. On the highest of those assumptions, the ethnic minority populations together (including ‘Other White’) would increase from 13% of the UK population in 2006 to 27 % by 2031 and to 43% by 2056. By the latter date over half the 0-4 age group would be members of the minority populations. That projection adopts the long-term fertility and mortality trends of  the ONS 2008-based Principal Projection and its overall level of net immigration. Alternative projections assume various lower levels of immigration. In the long run the growth of populations of increasingly complex mixed origins could make the definition and elaboration of ethnic groups as currently understood increasingly difficult, if not meaningless for a growing proportion of the future population.

Economic Consequences of international migration 

The supposedly beneficial economic consequences of international migration have been the subject of strong claims from official and other sources, particularly from business groups such as the CBI. This research, in conjunction with Professor Rowthorn, examined these claims critically from the viewpoint of fiscal, labour force, labour force and broader demographic effects of international migration to the UK in an international context. An analysis was published in 2004 in Population and Development Review (Paper 25) with further work by Rowthorn on fiscal consequences (Paper 27). Written and oral evidence on the economic consequences of immigration to the UK, was presented in 2008 to a House of Lords Select Committee on the  Economic Impact of Immigration (Working Paper 41), and in 2010 to the Migration Advisory Committee.

The consequences of declining population

While the demography of the UK is dominated currently by relatively rapid population growth provoked by substantial migration, many other European countries and some outside Europe face population decline. By comparison with the attention given to population ageing, the process and consequence of population decline have been little studied. They are generally assumed, on the basis of little evidence, to be unfavourable in respect of distribution, economy, labour force, investment, housing, security and international relations. A background paper is provided at Paper 15 and in the presentation 'The prospect of population decline'. A more rigorous analysis with Professor  Robert Rowthorn will be published early in 2011 in a Supplement to  Volume 37 of the journal ‘Population and Development Review’ (Demographic Transition and Its Consequences, ed. Ronald D. Lee and David Reher).