Effect of Census Processes on Non-response Rates and Person Counts
An increase in non-response rates is apparent for all census variables in the 2001 Census. Most of the change can be attributed to the increase in the proportion of System Created Records. These records are created during census processing for people for whom a census form has not been received and the collector believes that they have been missed from the Census count. This fact sheet discusses the factors that might have contributed to the increase in Systems Created Records and the implications for non-response rates.
For private dwellings, most System Created Records are created where the collector has not been able to make contact with the household, yet believes that the dwelling was occupied on Census Night. Smaller numbers of System Created Records are due to situations where people indicate a desire to mail back a census form but do not do so, and where people refuse to complete a census form. The term 'non-contact' dwelling is used in this paper to refer to all these situations. The number of person records created for the non-contact private dwellings is based on the average number of people in private dwellings for that collection district.
In non-private dwellings (such as hotels, motels, etc), System Created Records are created where a person is listed on the dwelling summary sheet as being present on Census Night, but no census personal form has been received.
Systems Created Records have values imputed for age, sex, marital status and usual residence. Values for other variables are set to not stated or not applicable, depending on the imputed value for age. Almost 95% of System Created Records are created in non-contact dwellings. Compared with 1996, the proportion of 'non-contact' dwellings more than doubled from around 0.9% of all dwellings in 1996, to 2.0% in 2001.
System Created Records (SCRs): 2001 and 1996 Censuses
Non-contact Dwellings: 2001 and 1996 Censuses
Increase in SCRs, 1996 to 2001
% of SCRs
% of SCRs
Non-contact Dwellings and Unoccupied Dwellings
An unoccupied dwelling for census purposes is different from a vacant dwelling. For a dwelling to be counted as unoccupied in the census it need only be empty on Census Night itself. In situations where the collector has not been able to collect a form from a dwelling, the collector is faced with the choice of recording the dwelling as either non-contact or unoccupied.
Some of the reasons for the increase in non-contacts are as follows:
Increase in Non-contacts 1996 to 2001
% of Non-contacts
% of Non-contacts
- In the 2001 Census, collectors reported difficulty contacting some householders, especially where there were access problems such as with security buildings or gated communities;
- In suburban areas, growing community concerns about security make it increasingly difficult to judge whether the residents are absent or not. If contact cannot be made with a household on delivery, the census form is left in a discrete location where it can be recovered by the collector if the resident was away. In some cases these forms are being removed by friends or neighbours and the collector makes the assumption that the household is occupied (and a '"non-contact"') rather than unoccupied;
The ABS is analysing the results of a number of studies undertaken to investigate this situation. A Census Paper covering these issues in greater detail will be published in the first quarter of 2003.
- Different procedures applied in the 2001 Census for the treatment of apartment blocks with mixed occupancy which contained both units occupied by residents (either owner-occupied or rented long term) and units occupied only by short-term visitors. These are prevalent in resort areas such as the Gold Coast, but also in the CBDs of major cities. In 1996, these were inconsistently treated - sometimes as a single non-private dwelling and at other times as a number of private dwellings. In 2001, if there was any doubt, the collector was instructed to treat these apartment blocks as a number of private dwellings.