Dwelling occupancy status 2013 Census (information about this variable and its quality)

##Related variables

• Occupied dwelling type – dwellings that are occupied are further classified in the occupied dwelling type classification, according to whether they are private or non-private, and to their structure and function.

##Where the data comes from

Dwelling occupancy status data is derived from the count of all dwelling forms received and substitute forms created, plus the count of unoccupied dwellings and dwellings under construction, as determined by the census collector during the census collection phase.

Substitute dwelling forms are dwelling forms created by Statistics NZ where there was sufficient evidence that a dwelling was occupied but Statistics NZ had no corresponding dwelling form. Substitute forms are created to ensure every person and every dwelling is counted in the census.

##How this data is classified

Census output produced on this variable is described as 'Occupied dwellings, unoccupied dwellings, and dwellings under construction'. It has the following categories:

• Total occupied dwellings
• Unoccupied dwelling – residents away
• Unoccupied dwelling – empty dwelling
• Total unoccupied dwellings
• Dwellings under construction.

‘Total unoccupied dwellings’ is made up of the 'Residents away' and 'Empty dwelling' categories. It does not include dwellings under construction.

For further information about this classification, refer to the:

• 2013 Census data dictionary
• Statistical standard for dwelling occupancy status
• Classification Code Finder.

For background information on classifications and standards, refer to the Classifications and related statistical standards page.

##Subject population

The subject population for this variable are all dwellings.

The subject population is the dwellings to which the variable applies.

##Non-response and data that could not be classified

For this variable there is no non-response category or categories for data that could not be classified. This is because all dwellings are classified as ‘Occupied’, ’Unoccupied – residents away’, ‘Unoccupied – empty dwelling’, or as ‘Under construction’ by the census collector during the census collection phase.

##How this data is used

Data from this variable is used:

• to provide an indication of the housing stock available in New Zealand for habitation
• to monitor trends and developments in the housing stock
• to evaluate infrastructure requirements, such as transport, sewerage and water
• at a regional level to provide information on how communities are changing.

##Data quality processes

All census data was checked thoroughly during processing and evaluation, to ensure that it met quality standards and is suitable for use. These quality checks included edits.

All data must meet minimum quality standards to make it suitable for use.

Quality level

A quality level is assigned to all census variables: foremost, defining, or supplementary.

The overall count of dwellings is a foremost variable. Unoccupied dwellings and dwellings under construction are defining variables. Foremost variables are core census variables that have the highest priority in terms of quality, time, and resources across all phases of a census. Defining variables cover key subject populations that are important for policy development, evaluation, or monitoring. These variables are given second priority in terms of quality, time, and resources across all phases of a census.

##Quality assessment of data and data quality issues for this variable

Overall quality assessment

High: fit for use – with minor data quality issues only. 2013 Census variable quality rating scale gives more detail.

##Comparing this data with previous census data

This data is highly comparable with data from the 2006 and 2001 Censuses. Changes in the data over this time period can generally be interpreted as real changes. There may be a small component of change over time that is due to minor changes in the collection, definition, or classification of the data.

This data is highly comparable with previous census data rather than fully comparable due to some variations in data quality over time, including difficulties in data collection in high-rise apartments in inner-city areas (especially in Auckland). In 2006, for a significant proportion of these apartments it was not possible to determine whether those that appeared unoccupied were empty, whether the residents were away, or whether the apartments were in fact occupied. Several hundred apartments were affected by this problem. Research was undertaken after the 2006 Census to ensure the data was as accurate as possible. A certain proportion were classified as ’Occupied’, a certain proportion were classified as ‘Unoccupied and empty’, and a certain proportion were classified as ’Unoccupied with residents away’. The proportional split used was:

• Occupied: 30 percent
• Unoccupied and empty: 52 percent
• Unoccupied with residents away: 18 percent.

There were also difficulties with data collection in high-rise apartments in 2001, but to a lesser degree.

This issue will have had little effect on the comparability of the data at the national and broad regional levels, as high-rise apartments make up only a very small proportion of dwellings overall. However, it will have affected the comparability of the data for inner-city areas.

##Comparing this data with data from other sources

No alternative data source is available.

##Further information about this data

When using this data, be aware of the following:

• All vacant private dwellings that were damaged by the Canterbury earthquakes of 2010 and 2011 have been classified as 'Unoccupied, empty'. This included dwellings where the occupants had moved out while their home was being repaired, and dwellings that were to be demolished but were still standing at the time of the 2013 Census.

Contact our Information Centre for further information about using this variable.