An Improved Method for Estimating Immigration to Local Authorities in England and Wales

1. An Improved Method for Estimating Immigrationto Local Authorities in England and Wales Nigel Swier British Society of Population Studies (BSPS) Conference York, 7-9 September 2011

2. Overview • What is being improved? • Issues with producing sub-national immigration estimates • Previous approaches • Outline of new method • How is this new method an improvement? • Results (to be released on 17 November)

3. Mid-Year Population Estimates (MYEs):Cohort Component of Change Previous Year Resident Population “Age On” Add Natural Change (Births – Deaths) Add Net Internal Migration (Inflows – Outflows) Add Net International Migration (Immigration – Emigration)

4. Estimating Immigration • UN definition of long-term international migrant: “12 months or more” • Based mainly on International Passenger Survey (IPS) • Adjustments for: • Visitor/migrant ‘switchers’ • Asylum seekers

5. Using IPS to estimate immigration • National level IPS estimates are robust • Can not produce LA level estimates directly • Centralizing tendency

6. Improved Previous (2007) Current (2010) England and Wales Immigration Estimate (IPS) Region/ Country Distribute using 3 yr LFS average Split by Reason for Migration: Work, Study, Returning, Other Intermediate Geography Use 3 yrs of IPS data 2001 Census distribution Model-based distribution Distribute using most appropriate admin source Local Authority Immigration Estimates Evolution of LA Distribution Methodology • Doesn’t address weaknesses with other parts of the methodology • Modelling approach lacks transparency • Results are difficult to explain for some LAs • Uses distributions from admin data not counts. • Original concept developed by University of Leeds • Enhanced through ONS access to microdata: • Refining definitions • Minimizing double counting

7. Worker stream Student stream Returning Migrants UK Born Non-UK Born Other stream Children 17-59 60+ Migrant Workers Scan HESA (Higher Education) BIS/WG (Further Education) GP Patient Register: ‘Flag 4s’ Asylum Seekers (NASS) L2 2001 Census distribution Residual LTM Worker distribution STM Student Distribution/ estimate LTM Student distribution New Distributional Model Overview IPS England and Wales Estimate (plus switcher adjustments) Local Authority Immigration (LTIM) estimates

8. How is this method an improvement? • More transparent • Uses more timely data • Removes known biases • More accurate

9. LA correlations of immigration with APS foreign born (as % of England & Wales total)

10. Next Steps • Release on 17 November: • - Research paper explaining methods • - Indicative immigration (and emigration) estimates • - Indicative population estimates • - Impact assessment • No revisions before 2011 Census results • ONS intend to incorporate method into 2010-base SNPPs

11. Questions?

12. Distributing immigrant IPS flows: workers (first arrivals) Simon Whitworth (ONS) Jennifer Ford-Evans (ONS) Andrew Needham (DWP)

13. Outline • Recap of method • Use of the International Passenger Survey • Use of admin sources • Basic methodology • Additions to the methodology • Summary

14. Who are we distributing? International Passenger Survey Estimate (plus switcher adjustments) Worker flow Student flow Returning Migrants UK Born Non-UK Born Other flow Children 17-59 60+ Total long and short term migration Migrant Workers Scan HESA (Public Higher Education) BIS/WAG Data (ESOL/, Further Education) Flag 4: GP Patient Register Asylum Seekers (NASS) L2 Residual LTM Worker distribution STM Student Distribution/ estimate LTM Student distribution 2001 Census distribution LTIM LA estimate

15. Who are we distributing? All the long-term migrant workers in E&W each year. This total number is taken from the IPS.

16. Identifying LT migrant workers on the IPS Is the country of residence 12 months ago outside the UK? Not a Migrant NO YES

17. Identifying LT migrant workers on the IPS Is the country of residence 12 months ago outside the UK? Not a Migrant NO YES Is the migrant planning on staying in the UK at least 12 months? Short-term migrant or visitor NO YES

18. Identifying LT migrant workers on the IPS Is the country of residence 12 months ago outside the UK? Not a Migrant NO YES Is the migrant planning on staying in the UK at least 12 months? Short-term migrant NO YES Returning migrant Has the migrant lived in UK before? YES NO

19. Identifying LT migrant workers on the IPS Is the country of residence 12 months ago outside the UK? Not a Migrant NO YES Is the migrant planning on staying in the UK at least 12 months? Short-term migrant NO YES Returning migrant Has the migrant lived in UK before? YES NO Not a long-term worker Is the migrant aged 16+? NO YES

20. Identifying LT migrant workers on the IPS Is the country of residence 12 months ago outside the UK? Not a Migrant NO YES Is the migrant planning on staying in the UK at least 12 months? Short-term migrant NO YES Returning migrant Has the migrant lived in UK before? YES NO Not a long-term worker Is the migrant aged 16+? NO YES • Is the intended Reason for Visit one of? • Definite job to go to • Looking for work • Working Holiday • Business • Other but previous occupation not retired or houseperson • Accompanying/joining and previous occupation work Not a long-term worker NO YES

21. Identifying LT migrant workers on the IPS Is the country of residence 12 months ago outside the UK? Not a Migrant NO YES Is the migrant planning on staying in the UK at least 12 months? Short-term migrant NO YES Returning migrant Has the migrant lived in UK before? YES NO Not a long-term worker Is the migrant aged 16+? NO YES • Is the intended Reason for Visit one of? • Definite job to go to • Looking for work • Working Holiday • Business • Other but previous occupation not retired or houseperson • Accompanying/joining and previous occupation work Not a long-term worker NO LONG-TERM MIGRANT WORKER YES

22. What we are using to distribute • The Lifetime Labour Market Database(L2) and the Migrant Workers Scan (MWS) • Derived from the National Insurance and PAYE System (NPS) - a database with records of all National Insurance Number (NINo) registrations since 1975.

23. What the MWS is • The MWS is a subset of the NPS and contains information on all the overseas nationals in the NPS • It excludes any data about activities • Address at registration is used as proxy for address at arrival. • It includes both long-term and short-term migrants with no way to distinguish.

24. How is the MWS used in the methodology The MWS is used to get the total count of migrant NINo registrations in an LA.

25. What the L2 is • The L2 is a 1% extract of data from the NPS. • This 1% contains over 750,000 individuals. • The L2 holds detailed records for each tax year from 1975 including activity information. • Each record can have various data present.

26. How the L2 is used in the methodology The L2 is used to calculate the proportion of LT migrant workers in an LA.

27. Definitions and assumptions on the L2 • Address at registration is used to allocate a geography to a migrant. • Activity denotes residency • Ceasing activity denotes departure • Re-engaging with activity denotes re-arrivals

28. Types of LT migrants

29. Identifying LT migrant workers on the L2 Is the country of origin outside UK and are they coming from abroad? NO Not a Migrant YES (then migrant)

30. Identifying LT migrant workers on the L2 Is the country of origin outside UK and are they coming from abroad? NO Not a Migrant YES (then migrant) What is the inferred length of stay? Less than 12 months Short-term migrant Greater than12 months (then long-term)

31. Identifying LT migrant workers on the L2 Is the country of origin outside UK and are they coming from abroad? NO Not a Migrant YES (then migrant) What is the inferred length of stay? Less than 12 months Short-term migrant Greater than12 months (then long-term) Does the LT migrant have an employment/self-employment record, JSA record or Working Tax Credit? Not a long-term worker NO YES

32. Identifying LT migrant workers on the L2 Is the country of origin outside UK and are they coming from abroad? NO Not a Migrant YES (then migrant) What is the inferred length of stay? Less than 12 months Short-term migrant Greater than12 months (then long-term) Does the LT migrant have an employment/self-employment record, JSA record or Working Tax Credit? Not a long-term worker NO YES Are there 6 months or less between arrival and registration? Not a long-term worker NO YES

33. Identifying LT migrant workers on the L2 Is the country of origin outside UK and are they coming from abroad? NO Not a Migrant YES (then migrant) What is the inferred length of stay? Less than 12 months Short-term migrant Greater than12 months (then long-term) Does the LT migrant have an employment/self-employment record, JSA record or Working Tax Credit? Not a long-term worker NO YES Are there 6 months or less between arrival and registration? Not a long-term worker NO YES Is the LT migrant worker a “potential student”? LT worker who is also a student (Taken out to eliminate duplication between streams) YES NO

34. Identifying LT migrant workers on the L2 Is the country of origin outside UK and are they coming from abroad? NO Not a Migrant YES (then migrant) What is the inferred length of stay? Less than 12 months Short-term migrant Greater than12 months (then long-term) Does the LT migrant have an employment/self-employment record, JSA record or Working Tax Credit? Not a long-term worker NO YES Are there 6 months or less between arrival and registration? Not a long-term worker NO YES Is the LT migrant worker a “potential student”? LT worker who is also a student (Taken out to eliminate duplication between streams) YES NO LONG-TERM MIGRANT WORKER

35. Recap of methodology LT worker figure for LA “X” = MWS count in LA “X” x L2 proportion of LT workers in LA “X”

36. Recap of methodology International Passenger Survey Estimate (plus switcher adjustments) Worker flow Student flow Returning Migrants UK Born Non-UK Born Other flow Children 17-59 60+ Total long and short term migration Migrant Workers Scan HESA (Public Higher Education) BIS/WAG Data (ESOL/, Further Education) Flag 4: GP Patient Register Asylum Seekers (NASS) L2 Residual LTM Worker distribution STM Student Distribution/ estimate LTM Student distribution 2001 Census distribution LTIM LA estimate

37. Sample size issues Using the method just described, the 1% L2 sample size means that in some LAs, the proportion of workers is very variable over time. In these cases, the proportion could not be used directly at LA level.

38. Sample size issues • To compensate for this, we have applied the proportion of LT workers at a higher geography to those LAs that were deemed not sufficiently robust. • The proportion is applied to the MWS • Directly at LA level in the case of 59 LAs. • At NUTS 3 geography in the case of 203 LAs. • At NUTS 2 geography in the case of 114 LAs.

39. Sample size issues NUTS 2 in East of England: East Anglia Essex Bedfordshire and Hertfordshire NUTS 3 in East of England East Anglia Cambridgeshire Peterborough Norfolk Suffolk Essex Essex CC Thurrock Southend-on-sea Bedfordshire and Hertfordshire Luton Bedfordshire CC Hertfordshire

40. Sample size issues In the East of England, there are: 2 LAs which use the proportion at NUTS 2 level 42 which use the proportion of LT workers at NUTS 3 level 4 which use the proportion of LT workers directly at LA level

41. Reconciling IPS and L2 • The two groups of LT migrant workers (IPS and L2) were compared • Some differences in the country of origin breakdowns were discovered

42. Reconciling IPS and L2 Accounting for this, a “subcontinent weighting factor” was introduced based on the E&W subcontinent split. EU Aus/NZ RoW Asia LT workers L2 EU Asia Aus/NZ RoW IPS LT workers

43. Summary of methodology Calculate LT worker proportion in the L2 and apply to MWS count

44. Summary of methodology Calculate LT worker proportion in the L2 and apply to MWS count LT worker figure in each LA from L2 and MWS

45. EU Aus/NZ RoW Asia Summary of methodology Calculate LT worker proportion in the L2 and apply to MWS count Split into subcontinents LT worker figure in each LA from L2 and MWS

46. EU Aus/NZ RoW Asia Summary of methodology Calculate LT worker proportion in the L2 and apply to MWS count Split into subcontinents Calculate weighting factor from IPS subcontinent split and weight L2 based data L2/MWS E&W Before LT worker figure in each LA from L2 and MWS

47. EU Asia Aus/NZ RoW Summary of methodology Calculate LT worker proportion in the L2 and apply to MWS count Split into subcontinents Calculate weighting factor from IPS subcontinent split and weight L2 based data L2/MWS E&W After LT worker figure in each LA from L2 and MWS

48. EU Aus/NZ RoW Asia EU Asia Aus/NZ RoW Summary of methodology Calculate LT worker proportion in the L2 and apply to MWS count Split into subcontinents Calculate weighting factor from IPS subcontinent split and weight L2 based data Distribute each IPS subcontinent total using weighted L2/MWS distributions and sum together to get total LT worker counts by LA LT worker figure in each LA from L2 and MWS LT workers in each LA that sum to IPS E&W total

49. Any questions? ?

50. Using administrative data to distribute long-term international immigrant students to Local Authority (first arrivals) Helena Howarth and Sofie De Broe BSPS Conference (York): 7-9 September 2011