Our Population

Demographics are quantifiable characteristics of a given population.

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These characteristics provide a picture of the current population and of changes to the population over time (including future projections). The health and wellbeing status of the population is influenced by population structure and demographic change. Changes in the size and structure of the population can also have significant impacts on the natural, physical, economic, and social environments, including the demand for health and social services, cultural and recreational services, schools, transport, water, waste management, energy, and housing.

The New Zealand census is a key source of demographic information for the population. The most recent census was held on 6 March 2018 and had a lower than expected response rate, impacting the quality and coverage of some census variables. To adjust for missing information, Statistics New Zealand combined census form data and administrative data to create a census dataset with records for approximately 4.7 million people (approximately 1.4% less than the best estimate of the population on census day). Further detail about data quality is provided in the metadata for each indicator.

This section presents 2018 Census data, other Statistics New Zealand population measures (such as population estimates and projections), and additional demographic data (such as deprivation and disability data) to show population structure and changes over time. Relevant local-level versus national-level comparisons are also highlighted.

Key trends within demographics

The greater Christchurch area experienced unprecedented population change following the Canterbury earthquakes in September 2010 and February 2011. The population of Christchurch City fell in 2011 and 2012 by 18,000 people, mainly due to people moving from Christchurch City to adjacent greater Christchurch areas (such as Selwyn and Waimakariri districts). This resulted in substantial population growth in the Selwyn and Waimakariri districts, while Christchurch City’s population took several years to re-bound, only recently surpassing the 2010 population of 376,300.

In 2019, the greater Christchurch usually-resident population was estimated to be 516,800, and by 2038 it is projected to reach 621,600. A majority of the greater Christchurch population resides in Christchurch City, which had an estimated usually-resident population of 387,700 in 2019, followed by Selwyn and Waimakariri districts (66,300 and 62,800, respectively). Over the next 20 years, Selwyn District is projected to experience the most growth of these three Territorial Authorities.

There are a number of important differences between population groups in greater Christchurch. For example, in 2018 Māori and Pacific ethnic groups had large younger populations, with just over half of Māori (50.7%) and Pacific peoples (53.6%) aged from 0 to 24 years, compared to Europeans with just 31.1 percent aged 0 to 24 years.

Both the New Zealand Deprivation Index (NZDep2018) and the Index of Multiple Deprivation (IMD18) demonstrate that fewer residents of greater Christchurch live in high deprivation areas when compared with New Zealand overall. However, there are substantial differences in deprivation between the three Territorial Authorities, with the deprivation distributions for Selwyn and Waimakariri districts showing a skew towards lower deprivation, compared to a more even distribution of deprivation in Christchurch City.

The census usually-resident population count includes residents who were present in New Zealand on census night.

This indicator presents the census usually-resident population change for greater Christchurch, the Territorial Authorities within greater Christchurch, and for New Zealand, using 2006, 2013, and 2018 Census data.

Table 1.1: Census usually resident population change for greater Christchurch, the Territorial Authorities within greater Christchurch, and New Zealand, 2006–2018  

 

Area

Population

Change 2006-2013

Change 2013-2018

2006

2013

2018

Number

%

Number

%

Selwyn District

33,645

44,595

60,561

+10,950

+32.5

+15,956

+35.8

Christchurch City

348,459

341,469

369,006

-6,987

-2.0

+27,537

+8.1

Waimakariri District

42,834

49,989

59,502

+7,155

+16.7

+9,513

+19.0

Greater Christchurch

424,935

436,056

489,069

+11,118

+2.6

+53,016

+12.2

New Zealand

4,027,947

4,242,048

4,699,755

+214,101

+5.3

+457,707

+10.8

 

The table shows that the greater Christchurch population grew overall between 2006 and 2018. The greater Christchurch total population was 489,069 at the 2018 Census, having increased 12.2 percent since 2013. The New Zealand population increased by 10.8 percent in the same time period. The increase in greater Christchurch was largely driven by population growth in Selwyn and Waimakariri districts (35.8 and 19 percentage points, respectively) between 2013 and 2018. In 2018, Selwyn District was the second-fastest growing Territorial Authority in New Zealand, after the Queenstown-Lakes District, which had increased by 38.7 percent since 2013. In the same time period, Christchurch City experienced an increase in population size of 8.1 percent (reaching 369,006 people in 2018). This is in contrast to the decline in the Christchurch City population noted between 2006 and 2013, likely due to the impacts of the 2010 and 2011 earthquakes [1].

This indicator presents the 2018 Census usually-resident population for greater Christchurch and the Territorial Authorities within greater Christchurch, by ethnic group. As this indicator reports ethnic group total responses, people who identify with more than one ethnic group are included in each ethnic group they identify with, meaning that the percentages sum to more than 100. While, the 2018 Census had a lower than expected response rate impacting the quality and coverage of some census variables, the 2018 Census ethnicity data is rated as high quality by Statistics New Zealand.

Table 1.2: Census usually resident population for greater Christchurch, and the Territorial Authorities within greater Christchurch, by ethnic group (total responses), 2018

Area European Māori Pacific Asian MELAA Other
Number % Number % Number % Number % Number % Number %
Selwyn District 54,102 89.3 4,788 7.9 1,014 1.7 3,858 6.4 525 0.9 1,071 1.8
Christchurch City 287,307 77.9 36,642 9.9 14,178 3.18 54,984 14.9 5,580 1.5 5,007 1.4
Waimakariri District 55,299 92.9 5,097 8.6 822 1.4 1,719 2.9 249 0.4 816 1.4
Greater Christchurch 396,708 81.1 46,527 9.5 16,014 3.3 60,561 12.4 6,354 1.3 6,894 1.4
New Zealand 3,297,664 70.2 775,836 16.5 381,642 8.1 707,598 15.1 70,332 1.5 58,053 1.2

 

The table shows that at the time of the 2018 Census, the European ethnic group was the largest in the greater Christchurch area, with 81.1 percent of the usually resident population (396,708 people) identifying as being of European ethnicity. Over nine percent of the greater Christchurch population identified as being of Māori ethnicity and 12.4 percent identified as being of Asian ethnicity. Pacific, Middle Eastern/Latin American/African (MELAA) and Other ethnicities were identified by 3.3 percent, 1.3 percent, and 1.4 percent of the population, respectively. When compared with New Zealand overall, greater Christchurch had smaller proportions of residents identifying as being of Māori, Pacific, Asian or MELAA ethnicity. For example, 16.5 percent of the New Zealand population identified as being of Māori ethnicity, compared to just over 9.5 percent in greater Christchurch. Of the three Territorial Authorities in greater Christchurch, Christchurch City had the most ethnically diverse population in 2018, with 77.9 percent of residents identifying as European, followed by Asian (14.9%), Māori (9.9%), and Pacific (3.8%), with MELAA and Other ethnicities identified by less than two percent each. Waimakariri and Selwyn districts had similar proportions of residents identifying with different ethnicities, however Selwyn District had a slightly higher proportion of residents identifying as being of Asian ethnicity compared with Waimakariri District (6.4% and 2.9%, respectively).

Data Sources

Source: Statistics New Zealand.
Survey/data set: Census of Population and Dwellings. Access publicly available data from the Statistics New Zealand website: www.nzdotstat.stats.govt.nz/wbos/Index.aspx?DataSetCode=TABLECODE
Source data frequency: Census conducted every 5 years.

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Population estimates produced by Statistics New Zealand estimate the annual change in the resident population. Population estimates are calculated using census data, net census undercount, residents temporarily overseas, and births, deaths and net migrations since census night [2]. Estimates are the best available measure of how many people usually live in an area each year and therefore are able to demonstrate annual fluctuations in the population, unlike the five-yearly census. This is valuable in the case of greater Christchurch, as the region has experienced unprecedented population change following the Canterbury earthquakes in September 2010 and February 2011.

This indicator presents the annual proportional change in estimated resident population for greater Christchurch, the Territorial Authorities within greater Christchurch, and New Zealand, using Statistics New Zealand data, 2009-2019.

The figure shows that greater Christchurch’s population has been increasing each year, since the decline seen in 2010–2011. In the year to June 2019, greater Christchurch’s estimated resident population was 516,800, which was an increase of 1.7 percent from the year to June 2018, similar to the national increase of 1.6 percent over the same time period. The greater Christchurch population is dominated by Christchurch City, which had an estimated resident population of 387,7000 in the year to June 2019 and as a result the two areas show a similar trend. Until recently, Selwyn District was New Zealand’s fastest growing Territorial Authority (at its peak growth, in the year to June 2017, the population increased by 6.4%), however the rate of population growth has slowed in the past two years. In the year to June 2019, Selwyn District had an estimated resident population of 66,300 (an increase of 4.7% from the previous year). In the last two years the population of Selwyn District has exceeded the population of Waimakariri District which, in the year to June 2019, was estimated to be 62,800.

Data Sources

Source: Statistics New Zealand.
Survey/data set: Subnational Population Estimates. Access publicly available data from the Statistics New Zealand website www.nzdotstat.stats.govt.nz/WBOS/Index.aspx?DataSetCode=TABLECODE7506
Source data frequency: Annually.

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Population projections produced by Statistics New Zealand estimate the future number of people living in an area. Projections are derived from population estimates and assumptions about future fertility, life expectancy, and net migration [2]. Projections provide planners with information about the probable size and demographics of the population, helping to ensure that governments, local councils, and communities have infrastructure and facilities to meet the short- and long-term needs of future populations [2].

This indicator presents the population projections for greater Christchurch, and the Territorial Authorities within greater Christchurch, for 2018 and 2048, using Statistics New Zealand data.

Table 3.1: Population projections for greater Christchurch, and by Territorial Authorities within greater Christchurch, 2018 and 2048

Area

Year

Total

Greater Christchurch

2018

508,400

2048

653,000

Christchurch City

2018

383,800

2048

463,500

Selwyn District

2018

63,300

2048

106,500

Waimakariri District

2018

61,300

2048

83,000

 

The table shows that by 2048 the greater Christchurch population is projected to reach 653,000. A majority of those people (463,500) will reside in Christchurch City. In 2018, Selwyn and Waimakariri districts had similar sized projected populations, however it is projected that Selwyn District will experience relatively more growth and reach a population size of 106,500 in 2048, compared with 83,000 for Waimakariri District.

Data Sources

Source: Statistics New Zealand.
Survey/data set: Subnational Population Projections: 2013 (base)-(2043) update. Access publicly available data from the Statistics New Zealand website www.stats.govt.nz/information-releases/subnational-population-projections-2013base2043-update
Source data frequency: Source data updated 2 to 3 years.

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Population pyramids illustrate the age distribution of a population in a particular country or region. Pyramids can be tailored to compare the age structure of population groups, for example by ethnicity or, as in this case, by gender.

This indicator presents the age and gender distribution of the population for greater Christchurch and New Zealand, using 2018 Census resident population count data.

Figures 4.1a and b show that the age and gender distribution of the greater Christchurch population was similar to that of New Zealand overall in 2018. Both areas had relatively high proportions in the 20- to 34-year age groups and in the 45- to 59-year age groups.

Figures 4.2 to 4.4 present the age and gender distribution of the Christchurch City, Selwyn District and Waimakariri District populations, using 2018 Census resident population count data.

The figures show that in 2018 Selwyn and Waimakariri districts had a smaller proportion of population aged between 20 to 39 years when compared with Christchurch City. This may reflect net out-migration of this age group to seek training and work opportunities. Waimakariri District had the largest proportion of people aged 65 years and over (18.9%), followed by Christchurch City (15%) and Selwyn District (11.5%).

Data Sources

Source: Statistics New Zealand.
Survey/data set: Census of Population and Dwellings. Access publicly available data from the Statistics New Zealand website www.nzdotstat.stats.govt.nz/wbos/Index.aspx?DataSetCode=TABLECODE
Source data frequency: Census conducted very 5 years.

View technical notes and data tables for this indicator.

Age distributions by ethnicity are useful to identify the age differences between ethnic groups.

This indicator presents the age distribution by ethnic group for greater Christchurch, using census usually-resident population count data, 2018. As this indicator reports ethnic group total responses, people who identify with more than one ethnic group are included in each ethnic group they identify with.

The figure shows that in 2018 the Māori and Pacific ethnic groups had a markedly different age structure from the European, Asian, Middle Eastern/Latin American/African (MELAA), and Other ethnic groups in greater Christchurch. In 2018, the Māori and Pacific ethnic groups had substantially younger populations, with just over half of Māori (50.7%) and Pacific peoples (53.6%) aged from 0 to 24 years. In contrast, under a third (31.1%) of the European ethnic group fell into this age range. Similarly, less than five percent of the Māori, Pacific, MELAA, and Asian ethnic groups were aged 65 years and over. Substantially higher proportions of the European and Other ethnic groups fell into this age group (17.2% and 9.5% aged 65 years and over, respectively). The younger age structure of the Māori and Pacific ethnic groups reflects both higher birth rates and lower life expectancy [3].

Data Sources

Source: Statistics New Zealand.
Survey/data set: Census of Population and Dwellings. Access publicly available data from the Statistics New Zealand website www.nzdotstat.stats.govt.nz/wbos/Index.aspx?DataSetCode=TABLECODE
Source data frequency: Census conducted every 5 years.

View technical notes and data tables for this indicator.

The number of greater Christchurch residents belonging to the Māori ethnic group increased by 12.4 percent between 2006 and 2013, from 30,591 to 34,371 [4]. The 2013 Census asked those who identified as being of Māori descent if they knew the name(s) of their iwi [5]. As Māori often affiliate with more than one iwi, people are included in each iwi they identify with.

The lower-than-expected response rate for the 2018 Census particularly affected the iwi affiliation variable. Statistics New Zealand will not release official statistical counts of iwi from the 2018 Census due to the poor quality of the data. Therefore, this indicator continues to present the ten most prevalent iwi affiliations among Māori descendants living in the greater Christchurch area, using census iwi (total response) data, 2013.

Table 6.1: Ten most prevalent iwi affiliations among Māori descendants living in the greater Christchurch area, 2013

Iwi

Greater Christchurch

Ngāi Tahu / Kāi Tahu

12,246

Ngāpuhi

4,689

Ngāti Porou

3,582

Ngāti Tūwharetoa

1,593

Waikato

1,452

Tūhoe

1,278

Ngāti Maniapoto

1,128

Ngāti Kahungunu ki Te Wairoa

1,065

Te Arawa

987

Te Atiawa (Taranaki)

771

 

The table shows that Ngāi Tahu/Kāi Tahu was the most common iwi affiliation in greater Christchurch with 12,246 people indicating an affiliation in the 2013 Census. Ngāpuhi and Ngāti Porou were the next most common iwi affiliations with 4,689 and 3,582 people respectively.  

Data Sources

Source: Statistics New Zealand.
Survey/data set: Census of Population and Dwellings. Access publicly available data from the Statistics New Zealand website www.nzdotstat.stats.govt.nz/wbos/Index.aspx?DataSetCode=TABLECODE248
Source data frequency: The 2018 Census iwi affiliation data will not be released by Statistics New Zealand. The next census will be conducted in 2023.

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The New Zealand Deprivation Index 2018 (NZDep2018) is a small-area measure of deprivation used to describe the deprivation experienced by groups of people [6]. NZDep2018 combines nine socio-economic variables from the 2018 Census, which represent eight deprivation factors: income, employment, communication, transport, support, qualifications, living space, and home ownership [7]. A weighted sum of these variables is calculated for the whole of New Zealand and to consider the deprivation distribution of different populations (such as ethnic groups and geographical populations). The NZDep2018 assigns each small-area in New Zealand a deprivation score. Based on these scores, areas are distributed into ten deciles, decile 1 indicates that an area is in the least deprived 10% of areas in New Zealand and decile 10 indicates that an area is in the most deprived 10% of areas in New Zealand. As an area measure of deprivation, NZDep2018 does not measure deprivation at an individual level.

Following the Canterbury earthquakes in 2010–2011, there was unprecedented population movement out of residential red zone areas in Christchurch City, particularly from more deprived areas of the city into less deprived areas. This redistribution may have caused an underrepresentation of deprivation as measured by NZDep2018 for Christchurch/Canterbury. Generally, increasing levels of deprivation are associated with higher mortality rates, and higher rates of many diseases [7].

This indicator presents the New Zealand Deprivation Index (NZDep2018) profile for greater Christchurch and by Territorial Authority.

The figure shows that the deprivation profile for greater Christchurch is skewed towards lower deprivation, with 50.8 percent of the population living in areas that have the least deprived NZDep scores (deciles 1-4) and 30.4 percent living in areas that have the four most deprived NZDep scores (deciles 7-10). Greater Christchurch has a relatively less deprived NZDep18 profile compared to New Zealand overall (for which, all deciles, by design, equal approximately 10%).

Figures 7.2 to 7.4 show that in 2018, a large proportion of residents from Selwyn District (89.0%) and Waimakariri District (64.4%) were living in areas with the four least deprived NZDep scores (deciles 1-4), along with much lower proportions living in areas with the four most deprived NZDep scores (deciles 7-10), at 4.6 percent and 16.7 percent, respectively. Christchurch City had a more even distribution across the deciles, with under half (42.3%) of the population living in areas falling into the four most deprived deciles and  just over a third (36.9%) living in areas falling into the four least deprived deciles.

Data Sources

Source: University of Otago.
Survey/data set: NZDep2018 Index of Deprivation, developed by Atkinson J., Salmond C. and Crampton P. 2014. Access publicly available data from the University of Otago website www.otago.ac.nz/wellington/departments/publichealth/research/hirp/otago020194.html
Source data frequency: Updated 5 yearly.

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The New Zealand Index of Multiple Deprivation (IMD) measures deprivation at the neighbourhood level using custom-designed data zones (on average a data zone has a population of 761 people) [8]. The IMD consists of seven domains of deprivation (income, employment, crime, housing, health, education, and access to services) and includes 28 indicators which have been created using routinely-collected data from government agencies, as well as census data [9]. The seven domains are weighted based on their relative importance to socioeconomic deprivation, adequacy of their indicators, and robustness of the data they use [9].

Data zones are ranked from 1 (least deprived) to 6,181 (most deprived) and grouped in five quintiles (quintile 1 represents the 20% least deprived data zones in New Zealand; while quintile 5 represents the 20% most deprived data zones in New Zealand) [8]. A strength of the IMD is that domains can be used in combination or individually, therefore users are able to see what health or social outcomes are driving deprivation within a given geographical area [9]. Like the New Zealand Deprivation Index (NZDep), the IMD is a small-area measure of deprivation: it does not measure the deprivation circumstances of individuals, and therefore not everyone living in a deprived area is deprived [9]. However, a particular strength of the IMD is that users can compare areas that share the same level of overall deprivation (for example Quintile 5) in a geographical area and explore whether the drivers of deprivation (such as the domains) are the same or different.

This indicator presents the proportion of data zones in each quintile of deprivation by overall IMD rank for Christchurch City, Selwyn District, and Waimakariri District.

The figure shows that Selwyn and Waimakariri districts had low levels of overall IMD deprivation with zero percent and 17.5 percent of data zones in those districts falling into the two most deprived quintiles (quintiles 4 and 5), respectively. More than a third (36.0%) of data zones in Christchurch City fell into quintiles 4 and 5, which was less than the national proportion (40%). Selwyn District had the highest proportion of data zones in the least deprived quintiles (quintiles 1 and 2) at 93.6 percent, followed by Waimakariri District (58.1%) and Christchurch City (44.1%).

Data Sources

Source: The University of Auckland.
Survey/data set: Index of Multiple Deprivation developed by Exeter et al 2017 and licensed by The University of Auckland for re-use under the Creative Commons Attribution 3.0 New Zealand licence. Access publicly available data from the University of Auckland website www.fmhs.auckland.ac.nz/en/soph/about/our-departments/epidemiology-and-biostatistics/research/hgd/research-themes/imd18.html
Source data frequency: The 2018 IMD will be updated following the 2023 Census.

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Long-term health condition or disability status has been measured in the Canterbury Wellbeing Survey since baseline (2012) [10]. The survey asks respondents whether they have a long-term health condition or disability (lasting 6 months or more) that stops them from doing everyday things that other people can do [11]. Over the time-series of the survey, respondents who have indicated having a long-term health condition or disability have also had poorer outcomes across a number of other survey measures, relating to both wellbeing status and to access to the determinants of wellbeing (for example overall quality of life, emotional wellbeing, loneliness or isolation, self-rated health, stress, ease of access to suitable transport for daily activities, ease of access to the natural environment, and household income meeting everyday needs) [11].

This indicator presents the proportion of those 18 years and over who responded to the 2020 Canterbury Wellbeing Survey indicating that they have a long-term health condition or disability.

The figure shows that, in greater Christchurch, the proportion of respondents living with a long-term health condition or disability was 17.8 percent in 2020. Waimakariri District had the highest proportion (20.2%) of respondents with a long-term health condition or disability, followed by Christchurch City (18.1%) and Selwyn District (13.7%). There were no statistically significant differences between the four areas.

Data Sources

Source: Canterbury District Health Board.
Survey/data set: Canterbury Wellbeing Survey to 2020. Access publicly available data from the Community and Public Health (Canterbury DHB) website www.cph.co.nz/your-health/wellbeing-survey/
Source data frequency: Annually.

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The New Zealand Disability Survey (2013) provides information about the number of disabled children and adults living in New Zealand. Disability was defined in the survey as “long-term limitation (resulting from impairment) in a person’s ability to carry out daily activities” [12]. A person (adult or child) may appear in more than one disability type.

This indicator presents the proportion of the Canterbury region and New Zealand population living in private households with a disability, by type, using New Zealand Disability Survey data, 2013.

Table 10.1: Proportion of the Canterbury region population living in private households with a disability, by type, 2013

Type of disability

Canterbury

New Zealand

Hearing

10%

8%

Seeing

4%

4%

Mobility

12%

12%

Agility

7%

7%

Intellectual

2%

2%

Psychiatric/  psychological

7%

5%

Speaking

3%

3%

Learning

4%

4%

Memory

4%

3%

Total with impairment

25%

23%

 

The table shows that the proportion of the Canterbury region population living with a disability was similar to the national proportion, both overall and by disability type. In Canterbury, mobility (12%) and hearing (10%) impairments were the most common disabilities, followed by agility (7%) and psychiatric/psychological (7%) disabilities.

Data Sources

Source: Statistics New Zealand.
Survey/data set: New Zealand Disability Survey 2013. Access publicly available data from the Statistics New Zealand website www.archive.stats.govt.nz/browse_for_stats/health/disabilities/DisabilitySurvey_HOTP2013/Commentary.aspx
Source data frequency: Previously 5 yearly, now 10 yearly.

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References

  1. New Zealand Treasury, McLeod K (2018) Where we come from, where we go – describing population change in New Zealand: Analytical paper 18/02. Wellington: New Zealand Treasury.
  2. Statistics New Zealand (2018) Frequently asked questions - population statistics updated 25 September 2018. Retrieved 15 November 2018 from www.stats.govt.nz
  3. Ministry of Health (2016) Health and independence report 2016: The Director-General of Health’s annual report on the state of public health. Wellington: Ministry of Health.
  4. Statistics New Zealand (2014) 2013 Census QuickStats about greater Christchurch. Wellington: Statistics New Zealand.
  5. Statistics New Zealand (2013) New Zealand Census of population and dwellings. Wellington: Statistics New Zealand.
  6. Salmond CE, Crampton P (2002) NZDep2001 index of deprivation. Wellington: Department of Public Health, Wellington School of Medicine and Health Science.
  7. Atkinson J, Salmond, C., & Crampton, P. (2019) NZDep2018 Index of Deprivation, final research report, December 2020. Wellington: Department of Public Health, University of Otago.
  8. Exeter D, Browne M, Chiang A, Crengle S, Zhao J, Lee A (undated) The 2018 New Zealand Index of Multiple Deprivation (IMD18): Indicators for social and health research in New Zealand. Brief report. Auckland: The University of Auckland.
  9. Exeter DJ, Zhao J, Crengle S, Lee A, Browne M (2017) The New Zealand Indices of Multiple Deprivation (IMD): A new suite of indicators for social and health research in Aotearoa, New Zealand. PLoS One 12.
  10. CERA (2012) CERA Wellbeing Survey 2012 Report, prepared by AC Nielsen for the Canterbury Earthquake Recovery Authority. AC Nielsen and the Canterbury Earthquake Recovery Authority.
  11. Canterbury DHB (2018) Canterbury Wellbeing Survey, June 2018: Report prepared by Nielsen for the Canterbury District Health Board and partnering agencies. Christchurch: Canterbury District Health Board.
  12. Statistics New Zealand (2014) Disability Survey: 2013. Wellington: Statistics New Zealand.