Use of an age only projection model The current household projections model breaks down the population by gender and marital status into the six categories of: Male, single, never married Female, single and never married Male, married Female, married Male, divorced or widowed Female, divorced or widowed A household representative rate is then projected across the projection period for each of these 6 groups, within 15 quinary age groups, resulting in 90 projected household representative rates. We propose that the split of the population by gender and marital status is removed, and the household representative rates are projected for quinary age groups only. There are three reasons for this: The split of the population by marital status was made possible by the marital status projections produced by ONS. The most recent set of marital status projections is the set published in 2010 and there are no immediate plans to update them. Therefore, over time, they will become less reliable. Social changes mean that marital status is likely to be less important as a driver of household formation patterns than in previous decades. The division of households by gender was only necessary due to the use of the old definition of head of household. If the 2011 Census definition for household reference person is used, there will be no requirement for a gender split. Using an age only projection model would reduce the number of projected household representative rates from 90 to 15. This change would make the projections easier to understand and use and it is anticipated that very little predictive accuracy would be lost in the process. Move to a one stage production approach The household projections are currently produced in two stages. Stage One uses Census data from 1971 to 2011 to project the household numbers for England, regions and local authorities. Stage Two uses Census data from 2001 and 2011 to project the number of households broken down by household type. The projections by household type produced in Stage Two are constrained to the projected household numbers produced in Stage One. We propose to use the Two approach only. This would mean that the household representative rates are projected using only the 2001 and 2011 Censuses, by age only, using the more recent Census definition of household reference person.
Use of an age only projection model The current household projections model breaks down the population by gender and marital status into the six categories of: Male, single, never married Female, single and never married Male, married Female, married Male, divorced or widowed Female, divorced or widowed A household representative rate is then projected across the projection period for each of these 6 groups, within 15 quinary age groups, resulting in 90 projected household representative rates. We propose that the split of the population by gender and marital status is removed, and the household representative rates are projected for quinary age groups only. There are three reasons for this: The split of the population by marital status was made possible by the marital status projections produced by ONS. The most recent set of marital status projections is the set published in 2010 and there are no immediate plans to update them. Therefore, over time, they will become less reliable. Social changes mean that marital status is likely to be less important as a driver of household formation patterns than in previous decades. The division of households by gender was only necessary due to the use of the old definition of head of household. If the 2011 Census definition for household reference person is used, there will be no requirement for a gender split. Using an age only projection model would reduce the number of projected household representative rates from 90 to 15. This change would make the projections easier to understand and use and it is anticipated that very little predictive accuracy would be lost in the process. Move to a one stage production approach The household projections are currently produced in two stages. Stage One uses Census data from 1971 to 2011 to project the household numbers for England, regions and local authorities. Stage Two uses Census data from 2001 and 2011 to project the number of households broken down by household type. The projections by household type produced in Stage Two are constrained to the projected household numbers produced in Stage One. We propose to use the Two approach only. This would mean that the household representative rates are projected using only the 2001 and 2011 Censuses, by age only, using the more recent Census definition of household reference person.
2017%20HP%20Consultation%20paper%202401V0.8.docx