1. Sub-National Projections for Scottish areas
William Howes
@NatRecordsScot

2. Overview Background Sub-national population projections
Other population projections
Household projections
Future developments
@NatRecordsScot

3. Projections in Scotland
Background
Projections in Scotland
ONS produce the national population projections for Scotland
NRS then produce sub-national population projections for council areas, health boards, national parks and strategic development planning authorities
The household projections are then produced, using the population projections as one of the inputs
There are:
32 Council areas;
14 NHS Board areas;
2 National Park areas; and
4 Strategic Development Planning areas.
@NatRecordsScot

4. Background 2016-based projections in Scotland
National population projections October-November 2017
Sub-national population projections Spring 2018
Household projections Summer 2018
@NatRecordsScot

5. Sub-national Population projections Cohort component method
Current Population
Special Population
Age On
Natural Change
Net Migration
Special Population
New Population
@NatRecordsScot

6. Sub-national Population projections Births and Deaths
To calculate projected births/deaths we multiply:
Population at risk
Local Scaling Factor
Age-Specific Fertility/Mortality Rates
@NatRecordsScot

7. Sub-national Population projections Special populations
Armed Forces Personnel
Prisoners
Old Method
A ‘miscellaneous’ adjustment.
The change in armed forces personnel in the year prior to the projection.
New Method
Average of estimated special populations.
Removed before and re-applied after projecting each year.
@NatRecordsScot

8. Sub-national Population projections Migration method change
Migration Components:
International (INT) Migration
Rest of UK (RUK) Migration
Within Scotland (WS) Migration
Old Method
All Migration –
Single-Region
Net Migration Assumption
New Method
INT Migration –
Auto-Regressive Time Series
RUK and WS Migration –
Multi-Region Rates Based
@NatRecordsScot

9. Sub-national Population projections The Old Method
East Lothian
City of
Edinburgh
Midlothian
@NatRecordsScot

10. Sub-national Population projections International Migration
Total estimated
Total projected
for one year
Total projected
for one year
Estimated age distribution
Scaled projection
Area scaled
Other area
National projection
@NatRecordsScot

11. Sub-national Population projections RUK and Within Scotland
Migration between
City of Edinburgh
and
East Lothian
Migration between
East Lothian
and
Midlothian
Migration between
City of Edinburgh
and
Midlothian
@NatRecordsScot

12. Sub-national Population projections Results of method change
New Method Projects Higher Population
New Method Projects Lower Population
@NatRecordsScot

13. Sub-national Population projections Variant projections
Constrained to the equivalent variant projection produced by ONS for Scotland as a whole
Available variants for sub-national projections:
Variant Type
Fertility
Life expectancy
Migration
Principal projection
Principal
Standard 'single component' variants
High fertility
High
Low fertility
Low
High life expectancy
Low life expectancy
High migration
Low migration
Special case scenario
Zero migration outwith Scotland migration
Zero
@NatRecordsScot

14. Sub-national Population projections Variant projections
@NatRecordsScot

15. Sub-council area projections
Other Population
projections
Sub-council area projections
The aim of the project was to provide insight into potential future population and household trends within council areas
We think this is the first time small area projections have been produced for a whole country – experimental statistics
Percentage change in population
@NatRecordsScot

16. Alternative EU migration variants
Other Population
projections
Alternative EU migration variants
Attempt to give an indication of the impact of differing future EU migration levels
Other assumptions the same as the principal projection
Migration Assumptions
Net migration from the Rest of the UK (2039)
Net migration from overseas (2039)
Total Net migration (2039)
150 per cent future EU migration variant
5,500
13,400
18,900
Principal
9,500
15,000
50 per cent future EU migration variant
5,600
11,100
Zero future EU migration variant
1,800
7,300
@NatRecordsScot

17. Alternative EU migration variants
Other Population
projections
Alternative EU migration variants
This resulted in population growth being 2% lower in Scotland in the 50% future EU migration scenario by 2039
However, these variants do have limitations
@NatRecordsScot

18. Household projections Method overview
Take population projections.
Subtract population living in communal establishments, e.g. student halls, care homes.
Project forward information on household type (‘headship rates’), e.g. 1 adult, 2 adults plus children
Use three censuses (1991, 2001 and 2011).
Scottish Household Survey data for 2014 – weights
Constrain to the household estimates and Scottish total
@NatRecordsScot

19. Household projections Variants
@NatRecordsScot

20. Future Developments
Change in Scottish planning system. May have to project for different areas
Develop age-specific fertility/mortality rates for each area
Adapt the method to calculate sub-Council projections
@NatRecordsScot

21. Future Developments
Potential impact of Brexit on the projections – contributing to ONS consultation
Ongoing requirement for EU variants – depends what variants are produced in the NPPs
Would be difficult to model the impact of Brexit at council level for the sub-national projections
@NatRecordsScot

22. Thank You
Sub-National Population Projections homepage:
Household Projections homepage:
Contact us at:
@NatRecordsScot