Reviewing household estimates for Scotland

1. Reviewing household estimates for Scotland Esther Roughsedge General Register Office for Scotland (GROS) www.gro-scotland.gov.uk/statistics/library/household-estimates-projections/index.html

2. Summary • In 2004-05, we reviewed our household estimates method. • Considered 3 approaches: • Stock-based (previous approach) • Population-based (≈ DCLG approach) • Council Tax-based (chosen approach)

3. Background to household estimates • Household estimates and projections are used for planning housing and service provision. • Scotland’s overall population is not changing greatly. • But households are increasing at 1% per year. • Caused by smaller average household size (and ageing population). • Wide geographic variation across country.

5. Method 1 - stock-based household estimates

6. Method 1: Stock-based household estimates • Advantages • Appeared to track changes reasonably well between 1991 and 2001. • No new data collections required. • Disadvantages • Slow – collecting information from LAs took a long time. • Some concerns about data quality (lots of revisions). • Relied on Census for private sector vacants/2nd homes. • No information on household type. • Not available for sub-LA areas.

7. Method 2: population-based household estimates • Equivalent to household projections method (similar to DCLG approach). • Based on population estimates; • Subtract communal establishment population (from Census); • Project household composition information from the 1991 + 2001 Censuses. • By household type, age group and LA

8. Population-based household estimates • Advantages • Population estimates and household estimates will tie in together. • Will include household type and age group. • Disadvantages • Same weaknesses as household projections – rely on Census.

9. Method 3: Council Tax-based household estimates • For Council Tax billing, councils keep a record of all dwellings and any discounts/exemptions. • Vacant dwellings and 2nd homes are entitled to certain discounts/exemptions. • Can use this to estimate no. occupied dwellings (≈ households).

10. Council Tax-based household estimates • Advantages • Unlike other approaches, there is no ‘drift’ between Censuses. • Far more timely. • Can include additional information on second homes/vacant properties. • Same method used to produce neighbourhood-level household estimates.

11. Council Tax-based household estimates • Disadvantages • If Council Tax is scrapped or substantially changes, we may lose this data collection. • Figures don’t exactly match the Census (e.g., don’t include shared households), so we anchor results to Census. • Little information on household type.

12. Conclusion • We wrote to each council in Scotland • Reasons for review and advantages and disadvantages of each approach. • Data and charts showing time series data using each approach. • Discussed with Household Analysis Review Group. • Concluded that Council Tax-based approach was best, mainly because it avoids ‘drift’ between Censuses and allows small area household estimates to be developed.

13. Any questions?