Household Projections for Scotland:2000-Based
3) Short Description of the Methodology
Household projections are produced approximately every 2 years. Their purpose is to give an indication of possible future numbers of households if trends observed in the past continue. It is important to realise that projections are not forecasts. The calculation of projected household numbers involves using the following two main sources of information:
- Population projections produced by the General Register Office for Scotland (GROS) give an indication of possible future trends in population. Estimates of the numbers of persons living in communal establishments are subtracted from the total population figures to produce projections of the numbers of person living in private households.
- Data on households from previous Censuses of Population can be used to identify trends which have taken place in household formation in the past. Census information is available for the years 1971, 1981 and 1991. This historic information is used to project possible future trends. For this set of household projections, the 1981 and 1991 Censuses of Population have been used ( see Annex A.4 for details of other methods tried).
The household projections are then calculated by applying projected trends in household formation, derived from the census information, to projections of the numbers of persons in private households, derived from the GRO population projections (Please see Annex A for further information).