Subnational Family and Household Projections 2018-base

Overview of changes to the 2018-base projections The content of the published outputs for these 2018-base projections is consistent with the 2013-base releases of national and subnational family and household projections (National family and household projections: 2013(base)–2038 update, Subnational family and household projections: 2013(base)–2038). However, methods used for structuring the historic living-arrangement-type data and for estimating the living-arrangement-type propensities at future time intervals are different to those used previously. Previous publications of family and household projections have been based on linear interpolation methods for determining plausible scenarios of future living-arrangement propensities given the historic trends observed by the census data. Propensities have been estimated for the output categories only and have not been informed by the distributions of the higher levels of living-arrangement categories and processes were executed separately for national and subnational projections. A key advantage of this new method is it allows for the simultaneous production of national and subnational projections, and provides scope for future enhancements. The changes to the 2018-base publication of family and household projections are summarised as: national and subnational projections of population by living-arrangement type, families by family type, and households by household type are published simultaneously both national and subnational projections of population by living-arrangement type, families by family type, and households by household type are produced for five-yearly intervals at 30 June 2018–2043 (previously, national projections were available at yearly intervals) national projections and regional council projections are produced by aggregating the projections for territorial authorities, including the areas split across regions living-arrangement-type categories have been derived based on consistent use of the 2001 to 2018 Censuses family coding and household composition information structuring the historic counts of living-arrangement-type information sequentially into progressively more detailed categories has potentially improved the quality of the estimated propensities used to produce the projections of population by living-arrangement type, and of families and households the modelled approach provides opportunities for future enhancements, such as incorporating uncertainty estimates of the living-arrangement-type propensities into the variants of the projections, and outputting projections of subpopulations by living-arrangement type. See 2018-base family and household projections: Data and methods for detailed data and methods used to produce the 2018-base family and household projections. en-NZ