subnational population projections for england
TRANSCRIPT
Subnational population projections for the West Midlands
Anthony Szary, Office for National Statistics
A presentation given at State of the Region: Implications of Population Change event, 31 March
2009.
This presentation forms part of the Observatory’s ongoing State of the Region dialogue between policy makers and researchers on the theme of
population change.
Subnational Population Projections
for West Midlands
Anthony Szary
Centre for Local & Regional StatisticsOffice for National Statistics
Context
• Subnational Population Projections for England produced every 2 years.
• Latest are 2006 based, projecting population, births, deaths, net migration forward for 25 years to 2031
• Used by:– Department of Health, CLG, DCSF– Local Authorities, Health Authorities– Regional/sub-regional bodies, academia etc
• Based on past trends and not policy based
• Use latest mid year population estimate as base
• Calculated at building brick (LA district) level
• Constrained to national projections
General Principles
Pp = Pc + B – D + Mw+ MI
• single year of age, gender and area
• repeated each projection year
Cohort Component Method: Basic Formula
• Ageing on
• Fertility
• Mortality
• Internal migration
• International migration
Stages in the model
• Births registrations form basis
• Local differentials calculated from observed data (past 5 years)
• Provides projected births by age of mother
• Controlled nationally – scaling local estimates
Fertility
• Uses death registrations
• Local differentials calculated from observed data (5 years)
• Projected numbers of deaths by age/sex
• Controlled nationally
Mortality
• Internal migration assumptions are derived using data from the Patient Register Data System (PRDS); GP registrations &NHSCR
• Produce matrices of movements by origin/destination by single year of age and sex
Internal Migration - 1
• Model out migration probability, fitting curves to historic data (5 years)
• Probability applied to population to give out migrants for that area
• Apply matrix to calculate in-migrants for each destination area
Internal Migration - 2
Typical Migration Age Profile
Age profile
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035
0.04
Age
0
Age
3
Age
6
Age
9
Age
12
Age
15
Age
18
Age
21
Age
24
Age
27
Age
30
Age
33
Age
36
Age
39
Age
42
Age
45
Age
48
Age
51
Age
54
Age
57
Age
60
Age
63
Age
66
Age
69
Age
72
Age
75
Age
78
Age
81
Age
84
Age
Prop
rtio
n of
mig
rant
s
• Migration streams dictated by data:– rest of world measured by International Passenger
Survey (IPS)– rest of UK (cross border), based on PRDS– rest of world that are seeking asylum or visitor
switchers (Home Office/IPS)
• Distribute national in and out migrants as per Mid Year Estimates method (propensity to migrate models utilising LFS data)
International Migration
• Each element is controlled to national totals
• Projected population is new base
• Repeat process for 25 years
Population Controls
• Aggregate building bricks to other geographies, such as:
– strategic health authorities– Government Office Regions
Aggregation
• Draft projections produced
• Consultation on first year migration assumptions
• Any adjustments applied
• Publication of final projections and supporting material
Processes
• Difficulties in measuring migration
• ONS has switched primary focus of IPS from the measurement of tourism to the measurement of migration
• Models to allocate international migrants more accurately being developed
Issues
• Projections are inherently uncertain
• A variant is simply a different set of assumptions applied to the same base data
• ONS sub national population projection variants will (resources permitting) be produced for the following different assumptions– High and low fertility– High and low mortality– High and low migration– Zero net-migration
Variants
Variants for England projections
Sub National Population Projections (English regions) - Total Population (000s)
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032
Tota
l Pop
ulat
ion
(000
s)
West Midlands North East North WestYorkshire & Humber East Midlands EastLondon South East South West
• Population of West Midlands projected to rise more slowly than most other regions
Population projection for West Midlands
NE
E
SE
Lon
NW
EMWM
Y&HSW
Source: ONS Sub National Population Projections 2006
21.0% 20.2% 19.7%18.5%
15.6% 15.6% 14.9%
11.4%10.2%
6.9%
0%
5%
10%
15%
20%
25%
EastMidlands
East South West Yorkshire &Humber
South East England London WestMidlands
North West North East
Popu
latio
n G
row
th (%
)Projected population growth between 2007 & 2027 English regions
Source: ONS Sub National Population Projections 2006
• Over next 10-20 years significant further ageing:
• Proportions in 10-30 age band to decline significantly
• Proportions in 65+ age band to rise significantly
Projected changes in Age Structure
2
3
4
5
6
7
8
0-4 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85+
Age Band
Prop
ortio
n of
Tot
al P
opul
atio
n %
2007
2017
2027
Population Profile Projections – 2007 to 2027 West Midlands
Source: ONS Sub National Population Projections 2006
• Proportion of WM population in 65+ age band to rise in line with, but remaining somewhat above, projections for England
• London continuing to have a much lower proportion in this age band, and the SW a significantly higher proportion
Ageing in comparison to other regions
10
15
20
25
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032
Prop
ortio
n of
Tot
al P
opul
atio
n %
West Midlands England North East North West Yorkshire & Humber
East Midlands East London South East South West
Proportion of population aged over 65 – English regions
Source: ONS Sub National Population Projections 2006
• Projections indicate ageing will be much more pronounced in certain Local Authorities
• eg. by 2027 proportions in 65+ age band projected to almost double in Redditch & Tamworth, but to rise only marginally in Birmingham & Coventry
Ageing by Local Authority
5
10
15
20
25
30
35
40
Sout
h Sh
rops
hire
Mal
vern
Hill
s
Her
efor
dshi
re, C
ount
y of
Brid
gnor
th
Stra
tford
-on-
Avo
n
Wyc
havo
n
Staf
ford
shire
Moo
rland
s
Sout
h St
affo
rdsh
ire
Osw
estr
y
Nor
th S
hrop
shire
Wyr
e Fo
rest
Shre
wsb
ury
and
Atc
ham
Bro
msg
rove
Staf
ford
Lich
field
Dud
ley
Solih
ull
New
cast
le-u
nder
-Lym
e
Wal
sall
Wol
verh
ampt
on
Rug
by
Nor
th W
arw
icks
hire
East
Sta
fford
shire
War
wic
k
Sand
wel
l
Stok
e-on
-Tre
nt
Nun
eato
n an
d B
edw
orth
Can
nock
Cha
se
Cov
entr
y
Wor
cest
er
Telfo
rd a
nd W
reki
n
Birm
ingh
am
Red
ditc
h
Tam
wor
th
Prop
ortio
n of
Tot
al P
opul
atio
n %
2007 2017 2027
Population & projections 2007 to 2027 Aged over 65 – West Midlands Local Authorities
Source: ONS Sub National Population Projections 2006
Contact details
Anthony SzaryCentre for Local and Regional StatisticsOffice for National StatisticsE [email protected] +44 (0)121 202 3256Web www.ons.gov.uk
Stephen HowarthDeputy Chief ExecutiveWest Midlands Regional ObservatoryE [email protected] +44 (0)121 202 3258Web www.wmro.orgBlog http://wmro.wordpress.com
Rosie DayResearch AnalystWest Midlands Regional ObservatoryE [email protected] +44 (0)121 202 3286Web www.wmro.orgBlog http://wmro.wordpress.com