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Ethnic change in the populations of the developed world. European Population Conference, Barcelona Thursday 10 July 2.30. D.A. Coleman and Sylvie Dubuc with the assistance of M.D. Smith. Department of Social Policy and Social Work, University of Oxford http://www.spsw.ox.ac.uk/oxpop.
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Ethnic change in the populations of the developed world.European Population Conference, BarcelonaThursday 10 July 2.30 D.A. Coleman and Sylvie Dubuc with the assistance of M.D. Smith. Department of Social Policy and Social Work, University of Oxford http://www.spsw.ox.ac.uk/oxpop
Projecting ‘foreign – origin’ populations: aims, concepts and problems • Major concerns of projection: decline and ageing, more recently human capital. • Differential fertility and migration now also transforming population composition. • Beginnings of a new demographic transition? First demographic transition out of phase in different populations • Implications for change in identity, culture, religion and politics, provision of services. • Problems of definition, data and projection.
Should projections assume rapid absorption of immigrant populations, or persistence of demographic and other distinctiveness? • ‘foreign origin or background’ – projections assume that ‘third generation’ becomes statistically invisible. • ‘Ethnic’ and ‘racial’ definitions imply potential permanence. • But mixed origin populations may eventually predominate.
Netherlands 2005 – 2050. Percent of population of foreign origin with and without migration, to show effect of ‘two-generation’ rule.
Norway 2005 – 2050. Projection of population of foreign origin, in two major categories (Percent of total population).
United States 1999 – 2100, projection by race and Hispanic origin.
Comparison of results of some European and US ‘foreign-origin’ projections.
Problems in projecting UK ethnic minority populations • Base population available from (1971), 1991 and 2001 censuses, Labour Force Survey etc. • But no vital registration by ethnic origin • Ethnic categories unstable. • Different (indirect) methods of estimating fertility give different answers. • No life tables available yet. • Migration data weak, no data by ethnic origin.
Completed Family Size by year of Birth and Ethnic Origin: GHS women born 1929 – 1984. N.B. latest cohort incomplete.
The ‘Own-Child’ Method of reconstructing birth-rates in past and current calendar years: Matching and allocation process.
TFR, 1965-2001: Comparing UK LFS own-child estimates of TFR with TFR from ONS registration data (total population).
TFR trends of UK ethnic minority populations 1965 – 2006data from Labour Force Survey by own-child method, 7-year moving averages. NB estimates before 1980 based on small numbers.
UK Pakistani TFR trends 1987 – 2006 unsmoothed,with confidence intervals to show range of error
Transition of UK Indian total fertility,1965 – 2006, annual estimates and 7-year moving average. Source: Labour Force Surveys, own-child method
Projection of fertility: UK Indian total fertility 1965 – 2006 and predicted to 2026 (asymptote 1.53)
Convergence in fertility? some persistent differentials in US fertility.Source: US Bureau of the Census.
Mortality • Mortality statistics: ASMRs difficult to compute: small numbers, under-20s deficient. • Chinese probably have lowest death rates. • IMR mostly higher. • For initial projections, England and Wales life tables used. projected to 2051 according to GAD assumptions. • Large and Ghosh (2006), and Rees (2008) used differential SMRs derived from geographical areas.
Estimated life table for immigrants born in the West Indies, 2001 (qx)
Estimating migration by ethnic origin, and the diversity of future trends. • UK migration data based on small sample, very broad categories only by citizenship, birthplace, country of origin. Ethnic origin inferred indirectly. • Recent trends and policy suggested further increase except asylum; these and official projections assume current level (unlikely). • Eastern European flow will fall with A8 growth; Labour migration will fall with recession; return migration to India; persistence of marriage migration; emigration drivers in Africa will continue.
UK population projections 2006-81, 2006-based, GAD Principal Projection and variant migration assumptions.
Some UK projections • Choices: to constrain or not to constrain? separate components or interactive? Migration numbers or rates? • Various other approaches: Large and Ghosh (2006); Rees (2008) and Bains (2006). • Diversity in fertility and migration • Mortality assumed to be England and Wales average • ‘Mixed’ populations begin to predominate.
Projection of UK populations 2001-2051, combined into three major groups.Assumptions: near-convergent fertility, constant migration, mortality as in GAD 2004-based PP.
Projection of UK ethnic minority populations 2001-51, grouped into ‘non-white’ and ‘white non-British’, to show the importance of migration.
UK population projection 2051 by age, sex and foreign / British ancestry.Assumptions for total population as GAD Principal Projection 2006 (net migration 190K; TFR 1.85)
Projection of UK Black populations and ‘Mixed’ (without intergenerational transfers) 2001-2051 (1000s).
Projection of selected UK Asian populations and ‘Other’, 2001-2051 (1000s).
Births of mixed origin as proportion of all births to mothers of different ethnic groups, UK, 1992-2001
Projection of Mixed populations, and Caribbean, with and without inter-generational contributions, UK 2001 – 2056(thousands).
Probabilistic projection 2001-2100: Mixed populations as a proportion of the total UK population
Conclusions • Projections of population by ethnic origin in UK are possible but with difficulty. • Must be regarded as indicators of implications of assumptions, not prophesies. • Most sensitive and unpredictable variable is migration, not fertility or mortality. • Migration policy must not be ignored. • Substantial growth, and re-alignment of relative size, of some groups is very likely. • ‘Mixed’ groups gaining in importance – multiple origins will eventually make ethnic categories less meaningful. • Next steps must include migration scenarios.
Logistic curve fitted to UK Chinese TFR data 1965 – 2006.Asymptotic TFR 1.285; 95% confidence intervals 1.084 and 1.487
Foreign-born Black-African inflow, 1986-2002 by sex and age upon arrival
Estimated Ethnic Composition of Births in England and Wales, 1993-2002 (n.b. scale)
Probabilistic projection of the UK white population 2001-2100