POPGROUP Slide 1 The Derived Forecasts module of the POPGROUP software Ludi Simpson, University of Manchester BSPS day meeting on household projection models, 16 th July 2012, LSE

POPGROUP Slide 2 UK industry standard for sub-national areas An integrated demographic model for planning and research –population, households, labour force, disability, … –local and central government information –small area and District, –District, County/Region/National –a demographic framework, data to fill it, and an analysis tool –historical series and new census data –estimates and forecasts –official projections and user’s own scenarios Excel platform

POPGROUP Slide 3 POPGROUP users organisations Mainly UK public sector Welsh Assembly for LA projections Scottish User Group supported by NRS Educational license: free for teaching Commercial sector use growing: the industry standard for UK local planning Local authorities

POPGROUP Slide 4 Popgroup management Developed collaboratively –Origins: 6 local authorities co-funded in 1999 –Ownership: Local Government Association since 2009 –£1500 POPGROUP, £1500 Derived Forecasts, one-off price Data Modules £450 a year, replicate official projections –Programming and technical support Ludi Simpson technical specification / support –Steering Committee – users, and Wales/Scotland reps, Andrew Rudd –Independent user group Charlotte Devereux –Web site and discussion list, –Training – online, 2-day annual course, manuals

POPGROUP Slide 5 POPGROUP & policy scenarios PopulationHouseholds Labour force - Not in households x Headship rates x Activity rates Revised migration Compare with housing supply Sharing, Vacancy rates, Second homes, Housing land Compare with jobs supply Unemployment, Commuting, Jobs creation

POPGROUP Slide 6 Presentation Demographic framework POPGROUP population forecasts framework Derived Forecasts framework –UK household projections frameworks Demonstration of Derived Forecasts model setup Data and analysis Demonstration of a household projections Data Module Demonstration of reports from a household projection Demonstration of a housing-led population forecast

POPGROUP Slide 7 POPGROUP population forecasts framework Standard cohort component methodology –Single year of age, to 90+ –Gross migration with two external areas –Schedules of births, deaths, migration may change over time –Special populations can be separate, eg Armed Forces Projection of multiple ‘Groups’, named by user –Districts in a Region, national areas, small areas within a district, ethnic groups within a district Accepts counts and rates, estimating the missing items –Counts take precedence: initial rates are re-estimated: –Time series of past data and forecasts –‘Forecasts’ with past population provide estimated rates and migration flows

POPGROUP Slide 8 Derived Forecasts framework Households = Population (adjusted to deduct those not in households) * age-sex-specific headship rate (for each household type) In defence of the ‘headship rates’ approach Household types can include size of household (Scotland, Wales) ‘Head’ can be a reference person, independent of changing cultural norms (England, Wales, Scotland) The same approach can use ‘membership rates’ in which non- heads are included in the output (Wales) –The number of households is derived by dividing by the number of people in a household type by its household size

POPGROUP Slide 9 Derived Forecasts framework Derived unitAdjustment to population CategoriesRateFactor Household (England) Communal establishments 17 household types Household representative - Household (Wales) Communal establishments 12, HH size included to 5+ Household membership Household size Household (Scotland) Communal establishments 7, HH size included to 3+ Household representative - Labour forceNoneEconomically active Economic activity - DisabilityNoneMotor, sight, …Disability rate- …

POPGROUP Slide 10 Derived Forecasts framework D =Derived Category Forecast P =Population ‘at risk’ Forecast R =Derived Category Rates a = age-group s = sex u = Sub-population y = year d = derived category g = group (usually an area, but can be an ethnic group or social group) D a,s,u,y,d,g = P a,s,u,y,g * R a,s,u,y,d,g / 100 Population Forecast Population forecast by age and sex Population Forecast by age and sex Derived Category Rates By age and sex (e.g. headship rates, disability rates) Derived Category Forecast Forecast for Derived Categories (e.g. Households, disability)

POPGROUP Slide 11 Derived Forecasts – Model Setup

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POPGROUP Slide 17 Using DF within POPGROUP cons.xls DFSupply.xls

POPGROUP Slide 18 The impact on population of a housing plan

POPGROUP Slide 19 DF - comparison of scenarios Example: Leeds Household impact of alternative population forecasts DFCompare.xls Households

POPGROUP Slide 20 Peter Boden Richard Culf

POPGROUP Slide 21 Observations POPGROUP –aims to satisfy local planning needs –replicates official ‘trend’ projections –is not restricted to any time or place –does not (yet) support projection of rates from a past time series Relies on work external to model –encourages users’ own policy-led scenarios and alternative demographic assumptions