Transcript Household Projections for Wales Tony Whiffen Presentation Outline • • • • Background Broad Methodology - Wales Wales Results / Issues Future Plans.

Household Projections for
Wales
Tony Whiffen
Presentation Outline
•
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Background
Broad Methodology - Wales
Wales Results / Issues
Future Plans
Background
• 2003-based household projections for Wales (2006)
– only available at regional level
– Last set under DCLG / Anglia Ruskin contract
• Opportunity to develop own methodology 2007-08
– Population and Households
– Local Authority level projections
– Not constrained
Wales NPP ≠ ∑ 22 Local Authority Projections
Background
• Membership method chosen 2008
• 2006-based household projections for Wales
published June 2009
• 2008-based set September 2010
• Variant projections
• Also National Park projections
• Using HOUSEGROUP WALES (forerunner
to Derived Forecasts)
Variant Projections
• Produced using available variant
population projections
– High: high fertility and low mortality
– Low: low fertility and high mortality
– Natural Change only / Zero Migration
Household Estimates
• Household Estimates  2010 (Feb 2011)
• Based on ONS population estimates not
Council Tax estimates
• Effectively ‘projected estimates’
– Populations – estimated
– Household membership rates - projected
Broad Methodology
• Use Membership Rates
• Household types based on size and presence
of children
• Census data used to project membership
rates
– APS considered but rejected
• Outputs broken down by household
type
The Membership Method
• Formula: h 
i
t 12

 ag 16,M ( popagi com magi )* yagti 
 

size
t
 ag 1, F

t 1
where hi = total households in year i
t = household type
ag = age and gender group
popagi = population in age and gender group ag in year i
commagi = communal establishment population in age and
gender group ag in year i
yagti = membership rate for age and gender group ag and
household type t in year i
sizet = household size for type t
Household Types
1 person
4 person (no children)
2 person (no children)
4 person (2+ adults, 1+ children)
2 person (1 adult, 1 child)
4 person (1 adult, 3 children)
3 person (no children)
5 + person (no children)
3 person (2 adults, 1 child)
5 + person (2+ adults, 1+ children)
3 person (1 adult, 2 children)
5 + person (1 adult, 4 + children)
Age Bands
0-4
40-44
5-9
45-49
10-15
50-54
16-18
55-59
19-24
60-64
25-29
65-74
30-34
75-84
35-39
85+
Membership Rates
• Data from 1991 and 2001 Censuses used
as APS/LFS data not suitable
• Two point exponential model used as a result:
yi  k  ab
xi
where i = the year
yi = membership rate in year i
k = 1 if y2001 ≥ y1991
0 if y2001 < y1991
a = y1991 – k
b = (y2001 – k)/(y1991 – k)
xi = (i – 1991)/(2001 – 1991)
Household Membership rate for age
and sex group
Membership Rates – Range
1
0.8
0.6
Rate 1
Rate 2
0.4
0.2
0
2008
2013
2018
2023
2028
2033
Household Membership rate for age
and sex group
Membership Rates: Largest
increases/decreases
1
0.8
0.6
Rate 3
Rate 4
0.4
0.2
0
2008
2013
2018
2023
2028
2033
Household projections by local authority, Wales, 2008-2033 (a)
2008
2013
2018
2023
2028
Thousands and per cent
Percentage
change,
2008 to 2033
2033
1,297.3
1,366.4
1,440.3
1,509.2
1,568.5
1,620.3
25
Isle of Anglesey
Gwynedd
30.6
51.9
32.0
53.8
33.4
55.7
34.5
57.5
35.3
59.0
35.8
60.3
17
16
Conwy
Denbighshire
50.7
43.1
52.8
45.8
55.0
48.5
57.0
51.2
58.7
53.5
59.9
55.3
18
28
Flintshire
64.1
67.1
69.9
72.2
73.8
74.6
16
Wrexham
57.2
60.7
64.1
67.4
70.2
72.7
27
Powys
59.0
63.0
66.7
70.0
72.7
74.6
26
Ceredigion
Pembrokeshire
Carmarthenshire
32.8
52.1
80.3
34.3
55.2
86.2
35.9
58.1
92.0
37.4
60.6
97.5
38.6
62.7
102.5
39.5
64.4
106.8
20
24
33
100.5
106.5
112.7
118.8
124.4
129.9
29
62.1
58.2
65.8
62.0
69.3
65.7
72.5
69.2
75.4
72.2
77.9
74.7
26
28
Wales(b)
Swansea
Neath Port Talbot
Bridgend
The Vale of Glamorgan
52.8
56.2
59.6
62.7
65.4
67.7
28
136.7
99.1
149.7
103.0
164.2
106.9
178.8
110.4
192.8
113.1
207.5
115.4
52
16
Merthyr Tydfil
23.9
24.9
25.8
26.5
27.0
27.5
15
Caerphilly
74.0
77.8
81.4
84.4
86.7
88.6
20
Blaenau Gwent
30.7
32.1
33.5
34.6
35.5
36.2
18
Torfaen
Monmouthshire
38.8
38.1
39.8
40.2
40.7
42.2
41.3
44.0
41.6
45.2
41.6
45.9
7
20
Newport
59.6
62.0
64.7
67.0
68.9
70.7
19
Cardiff
Rhondda Cynon Taf
(a) Based on the 2008-based Local Authority Population Projections
(b) Based on the 2008-based National Population Projection
Households (Thousands)
Projected Households, Wales
1,700
1,600
1,500
2003-based
2006-based
2008-based
1,400
1,300
1,200
1,100
1,000
2006
2011
2016
2021
2026
2031
Projected Total Population, Wales
Thousands
3,400
3,300
2006-based
projection
3,200
2003-based
projection
3,100
2008-based
projection
3,000
2010-based
projection
2,900
2,800
2,700
2006
2011
2016
2021
Source: Government Actuary’s Department / ONS
2026
2031
Net migration assumptions, 2006-based and 2008-based
LA Population Projections for Wales
Isle of Anglesey
Gwynedd
Conwy
Denbighshire
2006-based
2008-based Difference
+190
+210
+20
% Difference
in Projected
Households
2031
1%
+420
+940
+890
+250
+620
+640
-170
-320
-250
-5%
-6%
-4%
Flintshire
Wrexham
Powys
+130
+430
+1,190
-110
+440
+930
-240
+10
-260
-3%
1%
-4%
Ceredigion
Pembrokeshire
Carmarthenshire
+630
+850
+1,580
+410
+600
+1,400
-220
-250
-180
-7%
-4%
-1%
Swansea
Neath Port Talbot
Bridgend
+900
+830
+670
+960
+460
+610
+60
-370
-60
2%
-6%
-1%
Vale of Glamorgan
Cardiff
Rhondda Cynon Taf
+820
+630
+300
+570
+2,440
+130
-250
+1,810
-170
-3%
15%
-3%
Merthyr Tydfil
Caerphilly
Blaenau Gwent
-140
+140
+30
-40
+50
+30
+100
-90
+0
5%
-1%
0%
-40
-100
-60
-5%
+620
+220
+370
-190
-250
-410
-6%
-5%
Torfaen
Monmouthshire
Newport
Future Plans
• Look at Migration assumptions in
LA Population Projections
• Assess projections vs 2011 Census results
– Analysis of ‘actual’ vs ‘projected’ 2011 figures
– Third point to project household trends from
– New Assumption for Communal
Establishments population
Future Plans
• Shorter time lag between
LA Population and Household Projections
• Membership rate variants ?
Further information
www.wales.gov.uk/statistics
Email:
[email protected]
Phone: 029 2082 1595