“shaping australia” the development of a new statistical geography standard (the asgs)

“Shaping Australia”

The Development of a New Statistical Geography Standard (the ASGS)

Alister NairnDirector, Geography

alister.nairn@abs.gov.auPh: 02 6252 7759

Overview• Who cares? Media / political / user

interest in geographic classifications• Conceptual reasons for change.• Overview of the new standard and

differences with ASGC.

Who Cares?

Political and User Interest

Conceptual Reasons for Change?

1. Functional geography rather than administratively based

2. More stable units over time3. Units size optimised for output4. Higher spatial resolution - MBs5. Better support for “Non ABS geographies”

Functional area - Cooma

The ASGC structure - Unstable

Australia

StatisticalDivision

StatisticalRegion

StatisticalSubdivisions

StatisticalDistricts

MajorStatisticalRegion

StatisticalRegionSector

StateTerritory

Remoteness

CensusCollection Districts

Sectionof

State

UrbanCenter/Locality

LocalGovernment

Areas

StatisticalLocal Areas

LGAs – Unstable over Time

State Councils1910

Councils1991

Councils2007

Councils2010

NSW 324 176 152 152

VIC 206 210 79 79

QLD 164 134 157 74

SA 175 122 68 70

WA 147 138 142 139*

TAS 51 46 29 29

NT n/a n/a 64 16

Historical change in local governments across Australia

Units optimised for release and analysis of statistics

How do we determine the optimal size for statistical areas?

– What data is being released?– Confidentiality issues– Accuracy issues (surveys – modelled data)

•Difficulty when the classification had to fit into widely different sized LGAs

Higher spatial resolutionGeographic

Units

ASGC (2006) ASGS(Approximations)

Mesh Blocks n/a 347,627

CD vs SA1 38,704 54,805

SLA vs SA2 1,426 2,214

Better Support for other Non-ABS Geographies

Overview of ASGSStructure

SA1• Built up from whole Mesh Blocks• Smallest Census output unit• More homogeneous in character, but replaces CD

CD SA1

Number: 38,704 54,805

Average Size: 500 people 400 people

SA2

SLA SA2

Number: 1,426 2,214

Average Size: 15,000 people 10,000 people

Range: 0-150,000 people 0-25,000 people

• Based on functional areas and suburbs• Intercensal output unit• Replaces SLA as sub-LGA geography

Sydney SLAs

Sydney SA2s

Other geographic levels• SA3s

– medium sized regions– Ranging from 30,000 – 130,000

• SA4s– Used as Labour Force Regions– Ranging from 100,000 to 500,000

• Greater Capital City Statistical Areas– Defined using whole SA4s– Similar to Capital City SDs– Designed to provide consistent boundaries– Incorporating any likely growth over the next 20 years

SA3 and SA4

Perth Greater Capital City vs Capital City SD

Adelaide Greater Capital City vs Capital City SD

Brisbane Greater Capital City vs Capital City SD

Melbourne Greater Capital City vs Capital City SD

Availability of Statistics

Population Statistics Available

SA4 > 100,000 Labour force

Aggregations of other stats

SA3 20,000 – 130,000 Aggregations of data at SA2 and below (small regions)

SA2 3,000 – 25,000 Census, ERP, health, building approvals, tourism, Ag. Census

SA1 – (Census Output Unit)

Approx 400 Census data, SEIFA

MB 0 and about 70 Population, Dwelling counts

Availability of statistics for different levels of geographyPopulation Statistics

Available

Capital City / rest of state > Hundreds of thousands

Household survey data

CPI

Significant urban areas > 10,000 ERP

Census

UCL / section of state Localities 200 - 999

Urban Centres > 1000

Census

Remoteness Census

Health (AIHW)

Conclusions• ASGS is here!• Published in Volumes

– Main Structure MBs Dec 2010– Non ABS Structures & Indigenous July 2011– UCL and SUAs October 2012– Remoteness Late 2012

• Annual update of correspondences to non- ABS structures

• Effective from July 2011• Last ASGC is July 2012.• Implementation plans by SMAs being developed.