Quality Statement
This concept includes the two variables: legally registered relationship status and partnership status in current relationship.
Legally registered relationship status
Legally registered relationship status is a person’s status with respect to their relationship, which has been registered according to the laws and customs of the country in which they entered into that relationship. People in New Zealand can enter into two types of legally registered relationships: marriage and civil union.
Partnership status in current relationship
A person’s status with respect to their current relationship – either partnered or non-partnered.
Civil union
A civil union is the formalisation of a relationship between two people, regardless of gender.
Partnered
A partnered person is related to another person through:
- marriage or civil union
- a de facto relationship.
Same-sex marriage in New Zealand has been legal since 19 August 2013.
De facto relationship
A de facto relationship is between two people who usually reside together as a couple in a relationship in the nature of marriage or civil union, and who are not married to, or in a civil union with, each other.
Legally registered relationship status: High
Partnership status in current relationship: Moderate
Data quality processes section below has more detail on the rating.
Priority level 2
A priority level is assigned to all census concepts: priority 1, 2, or 3 (with 1 being highest and 3 being the lowest priority).
Relationship status is a priority 2 concept. Priority 2 concepts cover key subject populations that are important for policy development, evaluation, or monitoring. These concepts are given second priority in terms of quality, time, and resources across all phases of a census.
The census priority level for relationship status remains the same as 2018.
The 2023 Census: Final content report has more information on priority ratings for census concepts.
Census usually resident population count aged 15 years and over
‘Subject population’ means the people, families, households, or dwellings that the variable applies to.
Legally registered relationship status data is classified into the following categories:
Census Legally Registered Relationship Status V1.0.0 – level 1 of 2
Code | Category |
---|---|
11 | Married (Not Separated) |
12 | Civil Union (Not Separated) |
21 | Separated |
22 | Divorced or dissolved |
23 | Widowed or surviving civil union partner |
31 | Never married and never in a civil union |
99 | Not elsewhere included |
Legally registered relationship status uses a 2-level hierarchical classification with level 1 categories presented in the table above. The level 1 residual category ‘Not elsewhere included’ contains the residual categories ‘Response unidentifiable’ and ‘Not stated’. Follow the link above the table to examine the classification in more detail.
There has been a change to the classification since 2018. In the 2018 and prior censuses, a recode was used that categorised civil union as ‘not elsewhere included’ due to data quality issues.
Partnership status in current relationship data is classified into the following categories:
Partnership status in current relationship – Alternate Version CENSUS V1.0.0 – level 1 of 1
Code | Category |
---|---|
10 | Partnered, not further defined |
11 | Spouse |
12 | Civil union partner |
13 | De facto partner |
20 | Non-partnered, not further defined |
21 | Non-partnered, separated (marriage or civil union) |
22 | Non-partnered, divorced or dissolved (marriage or civil union) |
23 | Non-partnered, widowed or surviving civil union partner |
25 | Non-partnered, never married and never in a civil union |
99 | Not stated |
Partnership status in current relationship uses a 1-level flat classification as presented in the table above. Follow the link above the table to examine the classification in more detail.
This classification has also undergone a change since the 2018 Census. Historically, civil union partner was categorised as ‘partnered, not further defined’ due to quality issues. For the 2023 Census, it is included as its own category as it is fit for use.
Standards and classifications has information on what classifications are, how they are reviewed, where they are stored, and to how provide feedback on them.
Legally registered relationship status data is collected on the individual form (question 27 paper form).
Partnership status in current relationship data is derived from two questions on the individual form:
- living arrangements (question 17 on the paper form)
- legally registered relationship status (question 27 on the paper form).
There were differences in the way a person could respond between the modes of collection (online and paper forms).
Legally registered relationship status
On the online form:
- built-in routing functionality directed individuals in the subject population to the appropriate questions. Usual residents under 15 years and overseas visitors were routed past the question
- respondents could only select one response option for this question.
On the paper form:
- conflicting responses were possible; for example ticking both ‘I have never been legally married and I have never been legally registered in a civil union’ and ‘I am legally married’
- multiple responses to the question were possible. These were resolved through edits.
Living arrangements
On the online form:
- built-in routing functionality directed individuals in the subject population to the appropriate questions. Overseas visitors were routed past this question
- while this is a multiple response question, if a respondent indicated ‘I live alone’, no other living arrangement boxes could be ticked.
On the paper form:
- conflicting responses were possible; for example ticking both ‘I live alone’ and ‘my spouse/partner, eg husband’
- multiple responses to the question were possible. These were resolved through edits.
Data from the online forms may therefore be of higher overall quality than data from paper forms. However, processing checks and edits were in place to improve the quality of the paper form data.
Stats NZ Store House has samples for both the individual and dwelling paper forms.
Data-use outside Stats NZ:
- to examine changes in living arrangements over time, such as the increasing number of people who are not married but live with a partner
- in a variety of government planning and monitoring activities such as the development of housing, public health, and welfare systems
- to produce marriage rates for research and modelling purposes.
Data-use by Stats NZ:
- input into estimates of the not married and married populations to calculate marriage and divorce rates
- input into living arrangement type rates, including age-specific rates of being partnered, as a basis for family and household estimates and projections.
Legally registered relationship status
In the 2023 Census, alternative data sources were used for the first time for legally registered relationship status. Alternative sources were used to fill missing and residual census responses and responses that could not be classified or did not provide the type of information asked for.
The table below shows the distribution of data sources for legally registered relationship status data.
Data sources for legally registered relationship status data, as a percentage of census usually resident population count aged 15 years and over, 2023 Census | ||
---|---|---|
Source of legally registered relationship status data | Percent | |
2023 Census response | 83.6 | |
Historical census | 9.9 | |
2018 Census | 7.0 | |
2013 Census | 2.9 | |
Admin data | 1.9 | |
Deterministic derivation | 0.0 | |
Statistical imputation | 0.0 | |
No information | 4.6 | |
Total | 100.0 | |
Note: Due to rounding, individual figures may not always sum to the stated total(s) or score contributions. |
Where appropriate, responses from the 2018 and 2013 Censuses were used to replace missing or residual responses:
- If a respondent provided a historical census response and no more recent admin data was apparent, then their previous census response was used. If there was an admin data to show that their legally registered relationship status had changed, then the admin data was used to provide a response.
- If a respondent responded to ‘civil union’ but the admin data did not support this, the response was not considered valid. The response then went through alternative sourcing as described above.
- If alternative data sources were not available, then relationship status was set to ‘not stated’.
The following admin data sources were used, in order of priority:
- Department of Internal Affairs
- Ministry of Business, Innovation, and Employment.
Living arrangements
Alternative data sources were used for missing and residual census responses and responses that could not be classified or did not provide the type of information asked for. The table below shows the distribution of data sources for living arrangements data.
Data sources for living arrangements data, as a percentage of the census usually resident population count aged 15 years and over, 2023 Census | |
---|---|
Source of living arrangements data | Percent |
2023 Census response | 85.3 |
Historical census | 0.0 |
Admin data | 3.9 |
Deterministic derivation | 0.0 |
Statistical imputation | 0.0 |
No information | 10.8 |
Total | 100.0 |
Note: Due to rounding, individual figures may not always sum to the stated total(s) or score contributions. |
For any remaining missing or residual responses, the following admin data sources were used:
- Department of Internal Affairs
- Ministry of Social Development
- Ministry of Business, Innovation, and Employment
- Working for Families.
Partnership status in current relationship
Partnership status in current relationship is derived from legally registered relationship status and living arrangements data.
Editing, data sources, and imputation in the 2023 Census describes how data quality is improved by editing and how missing and residual responses are filled with alternative data sources (admin data and historical census responses) or statistical imputation. This webpage also contains a spreadsheet that provides additional detail on the admin data sources.
Missing and residual responses represent data gaps where respondents either did not provide answers (missing responses) or provided answers that did not fit predefined categories (residual responses).
Where possible, alternative data sources have been used to fill missing and residual responses in the 2023 and 2018 Censuses. Historically, all civil union data was output as ‘Not elsewhere included’.
Percentage of ‘Not stated' for the census usually resident population count aged 15 years and over:
Legally registered relationship status:
- 2023: 4.6 percent
- 2018: 16.7 percent
- 2013: 8.7 percent
Partnership status in current relationship:
- 2023: 4.2 percent
- 2018: 15.3 percent
- 2013: 7.0 percent
For output purposes, the residual category responses are grouped with ‘Not stated’ and classified as ‘Not elsewhere included’.
Percentage of ‘Not elsewhere included’ for the census usually resident population count aged 15 years and over:
Legally registered relationship status:
- 2023: 4.7 percent
- 2018: 17.4 percent
- 2013: 9.5 percent
Partnership status in current relationship:
Partnership status in current relationship does not have a ‘Not elsewhere included’ category.
Overall legally registered relationship status quality rating: High
Overall partnership status in current relationship quality rating: Moderate
Data has been evaluated to assess whether it meets quality standards and is suitable for use.
Three quality metrics contribute to the overall quality rating:
- data sources and coverage
- consistency and coherence
- accuracy of responses.
The lowest rated metric determines the overall quality rating.
Data quality assurance in the 2023 Census provides more information on the quality rating scale.
Data sources and coverage:
Legally registered relationship status: High quality
Partnership status in current relationship: Moderate quality
The quality of all the data sources that contribute to the output for the variable were assessed. To calculate the data sources and coverage quality score for a variable, each data source is rated and multiplied by the proportion it contributes to the total output.
The rating for a valid census response is defined as 1.00. Ratings for other sources are the best estimates available of their quality relative to a census response. Each source that contributes to the output for that variable is then multiplied by the proportion it contributes to the total output. The total score then determines the metric rating according to the following range:
- 0.98–1.00 = very high
- 0.95–<0.98 = high
- 0.90–<0.95 = moderate
- 0.75–<0.90 = poor
- <0.75 = very poor.
The proportion of legally registered relationship data sourced from 2023 Census forms, alongside the introduction of alternative data sources (historical census and admin data), resulted in a score of 0.95, leading to a quality rating of high.
Data sources and coverage rating calculation for legally registered relationship status data, census usually resident population count aged 15 years and over, 2023 Census | |||
---|---|---|---|
Source for legally registered relationship status data | Rating | Percent | Score contribution |
2023 Census response | 1.00 | 83.57 | 0.84 |
2018 Census | 0.94 | 7.03 | 0.07 |
2013 Census | 0.91 | 2.86 | 0.03 |
Admin data | 0.93 | 1.90 | 0.02 |
No information | 0.00 | 4.64 | 0.00 |
Total | 100.00 | 0.95 | |
Note: Due to rounding, individual figures may not always sum to the stated total(s) or score contributions. |
Partnership status in current relationship data is derived from legally registered relationship status and living arrangements. The metric one ratings for these are high (0.95) and poor (0.89) respectively, thus contributing to the data source and coverage score quality rating of 0.92.
Data sources and coverage rating calculation for partnership status in current relationship data, census usually resident population count aged 15 years and over, 2023 Census | ||||
---|---|---|---|---|
Source for legally registered relationship status data | Source for living arrangements data | Rating | Percent | Score contribution |
2023 Census form | 2023 Census form | 1.00 | 83.27 | 0.83 |
2023 Census form | Admin data | 1.00 | 0.00 | <0.01 |
2023 Census form | No information | 0.50 | 0.30 | <0.01 |
2018 Census | 2023 Census form | 0.97 | 1.35 | 0.01 |
2018 Census | Admin data | 0.97 | 1.52 | 0.01 |
2018 Census | No information | 0.47 | 4.16 | 0.02 |
2013 Census | 2023 Census form | 0.96 | 0.38 | <0.01 |
2013 Census | Admin data | 0.96 | 0.68 | 0.01 |
2013 Census | No information | 0.46 | 1.80 | 0.01 |
Admin data | 2023 Census form | 0.97 | 0.25 | <0.01 |
Admin data | Admin data | 0.97 | 0.53 | 0.01 |
Admin data | No information | 0.47 | 1.12 | 0.01 |
No information | 2023 Census form | 0.50 | 0.60 | 0.00 |
No information | Admin data | 0.50 | 0.68 | 0.00 |
No information | No information | 0.00 | 3.36 | 0.00 |
Total | 100.00 | 0.92 | ||
Note: Due to rounding, individual figures may not always sum to the stated total(s) or score contributions. |
Consistency and coherence:
Legally registered relationship status: High quality
Legally registered relationship status data is consistent with expectations across nearly all consistency checks, with some minor variation from expectations or benchmarks which makes sense due to real-world change, incorporation of other sources of data, or a change in how the variable has been collected.
The introduction of alternatively sourced data in 2023 has improved the quality of the data. Furthermore, using admin data for ‘Civil union (Not separated)’ resulted in the category being fit for use in 2023, whereas it was not fit in previous censuses.
Partnership status in current relationship: Moderate quality
Partnership status in current relationship data is mostly consistent with expectations across consistency checks. There is an overall difference in the data compared with expectations and benchmarks, which can be explained through a combination of real-world change, incorporation of other sources of data, or a change in how the variable has been collected.
The decrease in marriages during the COVID-19 pandemic and the general decline in marriages can be seen in the data and is reflective of real-world changes. The use of alternative data sources in 2023 greatly decreased the proportion of the ‘Not stated’ category, which contributed to an increase in proportions for most partnership status in current relationship categories.
Accuracy of responses:
Legally registered relationship status: High quality
Legally registered relationship status has only minor data quality issues. The quality of coding and responses within classification categories is high. Any issues with the variable appear in a low number of cases (typically in the low hundreds).
Some respondent error was still present in the data through a misunderstanding of civil unions, however this was mitigated through the use of admin data.
Partnership status in current relationship: Not applicable
Partnership status is a derived variable whose inputs are legally registered relationship status and living arrangements. The metric 3 rating for legally registered relationship status is ‘high’ and living arrangements is ‘moderate’.
Relationship status data (for both variables) can be used in a comparable manner to the 2018 and 2013 Censuses, with the addition that civil union data has been assessed as being fit for use for the first time since it was collected in the New Zealand census in 2006.
When using the data, users should be aware:
- as 2023 Census is the first time civil union data can be output, there is no time series data available
- partnership status in current relationship is derived from the legally registered relationship status and living arrangements questions. The legally registered relationship status question hasn’t changed since 2018, but the response options for the living arrangements question have. These response options were updated to include gender neutral options to align with the sex and gender changes.
- the introduction of alternative data sources in 2023 has increased counts in stated categories which will impact time series comparisons with previous censuses. When doing time series, it is recommended to use proportions rather than counts.
Comparison to other data sources
Although there are surveys and sources other than the census that collect relationship status data, data users are advised to familiarise themselves with the strengths and limitations of the sources before use.
Key considerations when comparing relationship status information from the 2023 Census with other sources include:
- Census is a key source of information on relationship status for small areas and small populations. Many other sources do not provide detail at this level.
- Census aims to be a national count of all individuals in a population while other surveys (such as the Household Labour Force Survey and the General Social Survey) measuring this variable are only based on a sample of the population.
To assess how this concept aligns with the variables from previous censuses, use the links below:
- Relationship status – 2018 Information by variable
- Relationship status – 2013 Information by variable
Contact our Information centre for further information about using this concept.