FEATURE ARTICLE: IMPLEMENTATION OF THE AUSTRALIAN STATISTICAL GEOGRAPHY STANDARD IN ABS BUILDING APPROVALS COLLECTION


INTRODUCTION

Geographic classification systems are important because they provide a common framework which enables the publication of statistics that are spatially comparable and integrated.

In December 2010, the Australian Bureau of Statistics (ABS) released a new geographic classification for statistical outputs, the Australian Statistical Geography Standard (ASGS), which will replace the current Australian Standard Geographical Classification (ASGC). The ABS will begin to implement the ASGS in July 2011.

The purpose of this article is to provide information about how the ASGS will be implemented in the Building Approvals collection. It also outlines the data items that will be available post-ASGS implementation.


WHY IS THE ASGS BEING IMPLEMENTED?

The ASGS was developed following a review of the ASGC that commenced in 2006 and involved consultation with a broad range of stakeholders. The ASGS has been designed to better meet the statistical needs of users and to address some of the shortcomings of the ASGC. In particular:

• ASGS regions are more consistent in terms of population size and represent functional areas
• The ASGS will remain stable for the 5 years between each Census

For further information see the ABS Geography portal.


IMPLEMENTATION

The ASGS will be implemented in Building Approvals, Australia (cat. no. 8731.0) from the July 2011 issue, scheduled for release on 30 August 2011. Building Approvals statistics will also continue to be produced using the current ASGC for each of the monthly releases in the 2011/12 financial year. Building Approvals data will no longer be available on an ASGC basis from the July 2012 issue. These changes will only affect statistics below the State/Territory level.

From the July 2011 issue, the release of fine geographic level outputs will no longer coincide with the publication release for Building Approvals, Australia (cat no. 8731.0). This is due to the increased processing required to produce outputs for both geographic classifications. Data cubes with finer geographic levels may be released up to 10 working days later than the publication and time series spreadsheets. The data, when available, will be accessible from the "Downloads" tab of the Building Approvals, Australia (cat. no. 8731.0) publication on the ABS website. Release dates for these data will be available in the ABS Release Advice. Release notifications will also be sent on the day of release through the ABS Email Notification Service.


Geographic level availability

Under the ASGS, Building Approvals data will be published at the Australia, State/Territory, Greater Capital City Statistical Area, Local Government Area (LGA) and Statistical Area Level 2 (SA2) levels. Further information about the ASGS and its different levels can be found in the publication Australian Statistical Geography Standard (ASGS): Volume 1 - Main Structure and Greater Capital City Statistical Areas, Australia, July 2011 (cat no. 1270.0.55.001). Non-ABS geographies including Local Government Areas will be released on 22 July 2011 in Australian Statistical Geography Standard (ASGS): Volume 3 - Non ABS Structures, July 2011 (cat no. 1270.0.55.003).

Some key differences between ASGC levels and ASGS levels are described in the table below.

Current ASGC level produced	New ASGS level produced	Differences
Australia	Australia	None
State/Territory	State/Territory	None
Capital City Statistical Division	Greater Capital City Statistical Area	Significant boundary and concept differences
Local Government Area	Local Government Area	LGA boundaries will be maintained as non-ABS structures of the ASGS
Statistical Local Area	Statistical Area Level 2	Significant boundary and concept differences

The geographic levels available over time are as follows:

Current - June 2011	July 2011 - June 2012	July 2012 onwards
Australia (ASGC)	Australia (ASGS)	Australia (ASGS)
State/Territory (ASGC)	State/Territory (ASGS)	State/Territory (ASGS)
Capital City Statistical Division (ASGC)	Capital City Statistical Division (ASGC)
	Greater Capital City Statistical Area (ASGS)	Greater Capital City Statistical Area (ASGS)
Local Government Area (ASGC)	Local Government Area (ASGC)	Local Government Area (ASGS)
Statistical Local Area (ASGC)	Statistical Local Area (ASGC)
	Statistical Area Level 2 (ASGS)	Statistical Area Level 2 (ASGS)

Implications for Local Government Area data

Under the ASGC, LGAs are made up of one or more Statistical Local Area (SLA). SLAs will be discontinued when the ASGS is implemented. The lowest geographical level for Building Approvals output published and available on an information consultancy basis, will be at the SA2 level. Due to the significant conceptual differences between SLA and SA2, the estimation of LGAs is not possible using SA2s. Consequently output data cubes at the LGA level will be produced independently of SA2 outputs.


Time series implications

Due to the differing geographic boundaries between ASGC and ASGS, time series for small area data will be affected. For Building Approvals data, the impact will be most evident at the SLA-SA2 levels and Capital City Statistical Division-Greater Capital City Statistical Area levels.

The release of Building Approvals outputs to both ASGC and ASGS over the 2011/12 financial year will provide a basis for analysis and comparison between the classifications for interested users. In addition, correspondences will be available from the Geography section of the ABS for users who wish to construct longer series using the ASGS.

Due to changes to capital city boundaries, Table 8 of the pdf publication will continue to be published using the ASGC (i.e. Capital City Statistical Division) for 2011/12 and will be changed to the ASGS (i.e. Greater Capital City Statistical Area) thereafter. Table 10 of the time series spreadsheets, "Dwelling units approved, By Capital City Statistical Division" will continue to be produced in 2011/12 but will be retired from July 2012 onwards. An additional time series spreadsheet, "Dwelling units approved, By Greater Capital City Statistical Area" will be produced from July 2011 onwards. The new time series identifiers associated with this spreadsheet will be published in the June 2011 issue.


INFORMATION CONSULTANCIES POST ASGS IMPLEMENTATION

The ABS has consulted clients and undertaken data quality examinations in order to determine what data will be available at ASGS levels on an information consultancy basis. A list of data items available on an information consultancy basis from July 2011 is provided on the "Downloads" tab of the Building Approvals, Australia (cat. no. 8731.0) publication on the ABS website under the data cubes heading.


FURTHER INFORMATION

For further information about the Building Approvals publication and new or existing consultancies please telephone the National Information and Referral Service on 1300 135 070. For questions about the implementation of the ASGS in the Building Approvals collection or changes to outputs please telephone the Building Approvals section on (08) 8237 7648. For information related to the ASGS see the geography portal www.abs.gov.au/geography or to obtain correspondence files please contact the Geography Section via email at geography@abs.gov.au or phone (02) 6252 6365.