Subnational family and household projections
This release contains updated 2001-base family and household projections for the 16 regional council and 74 territorial authority areas of New Zealand. These supersede the 2001-base subnational family and household projections released in August 2004. The projections have as a base the estimated resident population, estimated families and estimated households of each area at 30 June 2001, and cover the period to 2021 at five-year intervals.
The projections are neither predictions nor forecasts. They provide an indication of possible future changes in the number and composition of families and households in subnational areas. Statistics New Zealand makes no judgement on the relative merits of the projected changes.
Household numbers should not be confused with building activity or dwelling numbers. Households refer to private dwellings that are usually occupied by a person or group of people. Households therefore exclude non-private dwellings, unoccupied dwellings and dwellings which are not the usual residence of people (eg holiday homes, second homes).
Which projection series should I use?
Three alternative series (designated low, medium and high) have been produced for each area using different combinations of fertility, mortality, migration and living arrangement type assumptions. Users can make their own judgement as to which projection series is/are most suitable for their purposes. However, at the time of release, Statistics New Zealand considers the medium projection series the most suitable for assessing future family and household change. This series is consistent with series 5B of the national family and household projections (released 1 June 2005) and the medium series of the subnational population projections (released 28 February 2005).
The following analysis is based on the medium family and household projection series.
What has changed from the previous 2001-base projections?
Subnational family and household projections are updated every two to three years on average. These projections have been updated to incorporate the latest national family and household projections (released 1 June 2005) and the latest subnational population projections (released 28 February 2005). In turn, these are consistent with the latest national population projections (released 16 December 2004). Compared with the previous national population projections (series 4, released 24 October 2002), mid-range series 5 of the latest national population projections assumes:
- Net migration of 104,000 in the five years to 30 June 2006, 38,000 in the five years to 30 June 2011, and 50,000 in each subsequent five-year period. By comparison, the previous national population projections assumed net migration of 100,000 in the five years to 30 June 2006 and 25,000 in each subsequent five-year period. An average net migration level of 10,000 rather than 5,000 a year in the long-term better reflects recent and likely future migration trends, with changes in immigration policy during the last 20 years being a key factor behind the increase in average annual net migration.
- A slightly older net migration profile, with lower net inflow among the student ages (around 18 years).
- A rise in the total fertility rate from 1.97 in 2001 to 2.01 in 2004–2005, then dropping to 2.00 in 2006, 1.92 in 2011 and 1.85 from 2016. By comparison, the previous national population projections assumed the total fertility rate dropped to 1.89 in 2006 and 1.85 from 2011.
- Life expectancy at birth will increase to 80.7 years for males and 84.8 years for females in 2021. By comparison, the previous national population projections assumed life expectancy at birth of 80.3 years for males and 84.8 years for females in 2021.
The combined effect of these changes is that the New Zealand population is expected to reach 4.13 million in 2006, 4.29 million in 2011, 4.45 million in 2016 and 4.59 million in 2021 (series 5, 2004-base national population projections). By comparison, under series 4 of the 2001-base national population projections, the New Zealand population was expected to reach 4.11 million in 2006, 4.25 million in 2011, 4.38 million in 2016 and 4.51 million in 2021.
Differences in the projected size and age-sex structure of the population contribute to differences between the previous and latest family and household projections in the number, size and type of families and households. Series 5B of the latest national family and household projections indicates that the number of households will reach 1.55 million in 2006, 1.65 million in 2011, 1.75 million in 2016 and 1.84 million in 2021. By comparison, series 4B of previous national family and household projections (released 30 June 2003) indicated that the number of households would reach 1.55 million in 2006, 1.64 million in 2011, 1.73 million in 2016 and 1.82 million in 2021.
These subnational family and household projections also incorporate recent information at the subnational level, including subnational population estimates at 30 June 2004, and birth and death registrations to December 2004.
Households
The number of households in New Zealand is projected to increase by 400,000 (28 percent), from 1.44 million in 2001 to 1.84 million in 2021. A household is defined as one person usually living alone, or two or more people usually living together and sharing facilities (eg eating facilities, cooking facilities, bathroom and toilet facilities, a living area), in a private dwelling.
All 16 regions are projected to have more households in 2021 than in 2001. The largest increase is projected in the Auckland region, up 46 percent from 419,000 in 2001 to 614,000 in 2021. This accounts for half of the national growth in the number of households projected over this period. In comparison, the Auckland region is projected to account for 63 percent of New Zealand's population growth between 2001 and 2021. By 2021, 33 percent of all households in New Zealand will be in the Auckland region, up from 29 percent in 2001. The Tasman (40 percent), Bay of Plenty (35 percent) and Nelson (29 percent) regions are also projected to experience growth in the number of households exceeding the national average.
Among the 74 territorial authorities in New Zealand, 63 are projected to have more households in 2021 than in 2001. Six are projected to experience increases of over 50 percent: Queenstown-Lakes District (82 percent), Selwyn District (59 percent), Rodney District (58 percent), Manukau City (54 percent), Waimakariri District (52 percent) and Western Bay of Plenty District (51 percent). These areas are also projected to have the highest rates of population growth.
The greatest numerical growth in households over the 2001–2021 period is projected in the four cities in the Auckland region – Auckland City (63,000), Manukau City (48,000), North Shore City (27,000) and Waitakere City (27,000) – as well as in Christchurch City (27,000).
Household type
In 2001, there were 1.02 million family households in New Zealand. This number is projected to increase by 230,000 (23 percent), to reach 1.25 million in 2021. The number of households containing a family (or families) is projected to increase in 51 territorial authorities and decline in the remaining 23 areas. Changes in the number of family households are closely related to changes in the number of families in each area (nationally there was an average of 1.03 families per family household in 2001).
The family household is by far the most common household type, accounting for 71 percent of all New Zealand households in 2001. However, its share of all households nationally is projected to decline to 68 percent by 2021. A decline in share is projected for all territorial authorities, except Auckland City and Queenstown-Lakes District, where the family household share will remain stable.
The number of one-person households in New Zealand is projected to increase substantially from 333,000 in 2001 to 488,000 in 2021, up 154,000 (46 percent). The relatively large increase in this type of household is mainly due to the increasing population in the older ages, with 80 percent of the growth in one-person households occurring at ages 55 years and over. All territorial authorities are projected to have more one-person households in 2021 than in 2001, with numbers in Selwyn District and Queenstown-Lakes District doubling over the 20-year period. Increases of greater than 75 percent are also projected for Franklin District, Manukau City, Rodney District, Waimakariri District, Western Bay of Plenty District and Waitakere City.
One-person households will account for a greater share of households in all territorial authorities in 2021 compared with 2001. In 2021, the Buller (39 percent), Westland (37 percent) and Mackenzie (35 percent) districts are projected to have the highest shares of one-person households. These figures represent increases from 32, 29 and 28 percent, respectively, in 2001. The lowest shares of one-person households will be in Manukau City (17 percent), Selwyn District (20 percent) and Porirua City (20 percent). These shares are higher than the 2001 estimates for these areas of 15, 15 and 16 percent, respectively.
Other multiperson households (households containing more than one person, but not containing a family) are projected to increase nationally from 88,000 in 2001 to 102,000 in 2021. Growth in this household type is projected to slow between 2001 and 2021, with 70 percent of growth occurring in the first half of the period (2001–2011). The largest increases in the number of other multiperson households between 2001 and 2021 are projected in Auckland City (3,800), Manukau City (2,200) and Waitakere City (1,300). Increases of between 200 and 1,000 are projected in another nine territorial authorities, with little numerical change in the remaining areas.
Average household size
The average size of New Zealand households is projected to decrease from 2.6 people in 2001 to 2.4 people in 2021. Declining average household size is projected for all territorial authorities, and reflects an increasing proportion of one-person households and a decrease in the average size of family households. Average family size is projected to decline largely because of an increase in the proportion of 'couple without children' families (which contain two people) and a decrease in the proportion of 'two-parent' families (which contain about four people, on average). These trends are driven mainly by the general ageing of the population. The population aged 50 years and over is projected to increase by over 60 percent between 2001 and 2021, compared with almost zero growth for the population aged under 50 years.
Differences in average household size between territorial authorities reflect differences in family and household type, and to a lesser extent family size. In 2021, average household size is projected to be highest in Manukau City (3.1 people), and Porirua City, Waitakere City and Papakura District (all 2.7 people). These territorial authorities also had the highest average household sizes in 2001, of 3.3, 3.1, 2.9 and 2.9 people, respectively. These areas have relatively low proportions of one-person households and relatively high proportions of family households with children.
In contrast, the smallest average household size in 2021 is projected to be 2.0 people in the Buller and Westland districts. In 2001, the smallest average household size was 2.3 people in the Thames-Coromandel, Waitaki and Buller districts. These areas have relatively high proportions of one-person households and relatively low proportions of family households with children.
Household change compared with population change
The projections indicate that household growth is likely in all regions and most territorial authorities, including some areas projected to experience population decline. At the national level, the projected increase in the number of households (28 percent) between 2001 and 2021 is greater than the projected growth of both families (24 percent) and population (18 percent), reflecting the trend towards smaller average household size. The household growth rate is projected to exceed the population growth rate in all regions and territorial authorities.
The medium series of the 2001-base subnational population projections (released in February 2005) indicates that five regions – Gisborne, Taranaki, Manawatu-Wanganui, West Coast and Southland – are projected to have fewer people in 2021 than in 2001. However, all of these regions are projected to experience an increase in the number of households. Similarly, 33 territorial authorities are projected to have fewer people in 2021 than in 2001, but 22 of these are projected to have more households.
These trends are a further reflection of changes in the age structure of the population, with all territorial authorities projected to have more older people (65 years and over) in 2021. In contrast, the majority of areas are projected to have fewer children (0–14 years) in 2021.
Families
The number of families in New Zealand is projected to increase by 250,000 (24 percent) between 2001 and 2021, from 1.05 million to 1.30 million. A family refers to a couple, with or without child(ren), or one parent with child(ren), usually living together in a household.
Thirteen of the 16 regions in New Zealand are projected to have more families in 2021 than in 2001. The largest increase in the number of families is projected in the Auckland region, up 45 percent from 322,000 to 466,000. This accounts for 57 percent of the projected increase in the number of families at the national level. By 2021, 36 percent of all families in New Zealand are projected to live in the Auckland region, compared with 31 percent in 2001. The Tasman (33 percent), Bay of Plenty (29 percent) and Nelson (25 percent) regions are also projected to experience growth in the number of families above the national average. Fewer families are projected in the Southland, West Coast and Taranaki regions by 2021.
Among territorial authorities, 51 are projected to have more families in 2021 than in 2001, while the remaining 23 areas will have fewer families. Growth in the number of families is projected to slow at the national level over the projection period, and a similar pattern is likely for most subnational areas. This trend reflects the slowing of population growth and the changing age structure of the population. While 18 territorial authorities are projected to record a decrease in the number of families between 2001 and 2011, 29 are projected to record a decrease between 2011 and 2021.
The four areas projected to experience the highest percentage growth in the number of families between 2001 and 2021 are Queenstown-Lakes District (84 percent), Rodney District (52 percent), Manukau City (52 percent) and Selwyn District (51 percent). These are also the areas projected to have the highest percentage growth in population and households. The largest numerical increases in families between 2001 and 2021 are projected in Auckland City (45,000) and Manukau City (40,000), followed by Waitakere City (19,000), North Shore City (19,000) and Christchurch City (15,000).
Family type
At the national level, the number of 'couple without children' families is projected to increase by 53 percent, from 407,000 in 2001 to 623,000 in 2021. 'Couple without children' families include couples who will never have children, couples who will have children in the future, and couples whose children have left the parental home. The main factor behind the growth is the increasing number of people aged 50–90 years, where living in a 'couple without children' family is the most common living arrangement type. All territorial authorities are projected to have at least 10 percent more 'couple without children' families in 2021 than in 2001. The number of 'couple without children' families is projected to more than double in Queenstown-Lakes District (from 2,400 to 5,200) and Selwyn District (from 3,200 to 6,400) over this period.
The number of 'two-parent' families in New Zealand is projected to decrease from 446,000 to 427,000 over the 2001–2021 period. This is due to a decreasing likelihood of being in this living arrangement type at most ages, reflecting continued trends towards single parenting and fewer couples having children. However, 12 territorial authorities are projected to have more 'two-parent' families in 2021 than in 2001. These are areas projected to have significant population growth. Despite the increase in the number of 'two-parent' families in these areas, the share of families in this family type is projected to decrease for all territorial authorities – due to faster growth in the numbers of 'couple without children' families and 'one-parent' families.
Nationally, the number of 'one-parent' families is projected to increase by 28 percent, from 198,000 in 2001 to 254,000 in 2021. Increases are projected for 47 territorial authorities, with the highest in Queenstown-Lakes District (92 percent), Manukau City (65 percent), Selwyn District (62 percent) and Rodney District (60 percent). As children in families can be of any age, one-parent families include mature children living with an older parent.
By 2021, 'couple without children' families are projected to be the most common family type in nearly all territorial authorities. The exceptions are Manukau City and Porirua City, where 'two-parent' families will remain the most common family type. In 2001, 'two-parent' families were the most common family type for 39 territorial authorities, while 'couple without children' families were the most common family type for the remaining 35 territorial authorities.
For technical information contact:
Nick Thomson or Richard Speirs
Christchurch 03 964 8700
Email: demography@stats.govt.nz.