|Page tools: Print Page Print All|
CHAPTER 1 INTRODUCTION
PURPOSE OF THE NLI
The NLI is used within the ABS to assign geographic codes to statistical units in several collections including Health and Vitals and the Census of Population and Housing. It is also used by many clients and government agencies to code their own address information to the geographical units of the ASGC.
Date of effect
The NLI reflects the codes and names of the ASGC edition current at its release. Each edition of the ASGC becomes effective on 1 July of the year in question.
LOCALITIES AND STREETS
The NLI contains information about Localities across Australia and consists of two parts:
Definition of Locality
In order to keep the NLI as comprehensive as possible, the definition of ‘Locality’ has been made very broad. A Locality is defined as the name of a place where people live or work - or say they live or work.
A Locality may be treated as if it has wider boundaries than those which have been officially gazetted.
A Locality may exist across more than one ASGC area. In these instances, the Locality is described as being ‘split’. Split Localities are linked to the Streets Sub-Index where each street and its street number range is coded to its respective ASGC code.
CHAPTER 2 AUSTRALIAN STANDARD GEOGRAPHICAL CLASSIFICATION (ASGC)
MAIN STRUCTURE OF THE ASGC
The Main Structure of the ASGC is used to collect and disseminate a broad range of ABS social, demographic and economic statistics. These are statistics with a ‘where’ dimension.
The ASGC Main Structure code to which a Locality is coded has nine digits. It comprises codes representing the top four hierarchical levels of the Main Structure.
The four hierarchical levels are:
In this structure, the SLAs aggregate to form SSDs which in turn aggregate to form SDs and the SDs aggregate to form S/Ts. All levels cover the whole of Australia without gaps or overlaps.
Details of the ASGC are available in the publication Australian Standard Geographical Classification (ASGC) (Cat. no. 1216.0).
State/Territory (S/T) (1 digit code)
The S/T is identified by a unique one digit code and is the first digit or component of the nine digit ASGC code. The S/T is the largest spatial unit in the Main Structure. Codes for the States and Territories in Australia are as follows:
1 New South Wales
4 South Australia
5 Western Australia
7 Northern Territory
8 Australian Capital Territory
9 Other Territories
S/Ts consist of one or more SDs and cover the whole of Australia (as defined for statistical purposes) without gaps or overlaps. They encompass the geographic areas of the Australian States, mainland Territories and the external Territories of Christmas Island and Cocos (Keeling) Islands. ‘Other Territories’ is an aggregate, for statistical purposes, of the external Territories and Jervis Bay Territory.
Statistical Division (SD) (2 digit code)
SDs are large regional type spatial units and aggregate to form S/Ts. Any one SD consists of one or more SSDs. They cover, in aggregate, the whole of Australia without gaps or overlaps. The two digit SD code must be used with the relevant S/T code for unique identification Australia-wide.
Statistical Subdivision (SSD) (2 digit code)
SSDs are smaller regional type spatial units and aggregate to form SDs. Any one SSD consists of one or more SLAs. They cover, in aggregate, the whole of Australia without gaps or overlaps. SSD codes are unique within each SD. The two digit SSD code must be used with the relevant SD and S/T code for unique identification Australia-wide.
Statistical Local Area (SLA) (4 digit code)
The SLA is the smallest spatial unit for the compilation and publication of economic, social and demographic statistics other than those collected in population censuses. SLAs can be local government areas, or parts thereof, or any unincorporated area. They cover, in aggregate, the whole of Australia without gaps or overlaps. The four digit SLA code must be preceded by at least the S/T code for unique identification Australia-wide.
Example of ASGC code
The ASGC code 110051720 can be broken down as follows:
CHAPTER 3 LOCALITIES INDEX
The Localities Index is a comprehensive list of Localities across Australia together with their Australian Standard Geographical Classification (ASGC) Main Structure codes current at the time of release and postcodes.
Approximately 5% of the Localities listed lie across two or more Statistical Local Areas (SLAs) and are referred to as ‘split Localities’. Split Localities are those on the Localities Index which have more than one ASGC code.
Link to Streets Sub-Index
Addresses in split Localities can be coded to their correct SLA codes by means of the Streets Sub-Index (please see chapter 4).
LOCALITIES INDEX FILE FORMAT
The standard format for the Localities Index is a comma delimited ASCII text file with fixed length fields and a record length of 157 characters. This format is suitable for uploading to either micro or mainframe computers. The standard file format and example records are described below.
All names on the National Localities Index are in CAPITALS. Output files are sorted by S/T and Locality Name.
FIELD NAMES AND DEFINITIONS
The following field names and definitions describe the information contained in the Localities Index. The Localities Index is subject to other rules which govern data representation and these are explained in Appendix 1.
A Locality may be a city, town, suburb, neighbourhood or commonly used location name such as a large agricultural property or railway siding. Also included are some commonly used alias or unofficial Locality names. Where a Locality crosses an S/T border, the two sides of the border are recorded as two separate Localities. For example Williamsdale crosses the S/T border between New South Wales and the Australian Capital Territory and is shown on the NLI as follows:
The Property Indicator field was originally created to flag Localities that are properties (P) and/or Localities with no postal service (N). The N flag is no longer used as all Localities are now allocated a postcode. Current indicators in this field are:
P = property
S = railway siding
(blank) = default
Postcode 1 and Postcode 2
These fields record the Australia Post postcode(s) for the Locality. Generally Localities have only one postcode, however there are a small number of Localities where mail delivery is shared by two Post Offices. Recording the postcode in the National Localities Index helps to differentiate between Localities with the same name in the same State.
The S/T code indicates the State or Territory in which the Locality exists. Please refer to chapter 2, for more details on S/T.
ASGC Code Major SLA
The code of the Major SLA is an eight digit code made up of the Statistical Division (SD), Statistical Subdivision (SSD) and SLA codes (each of these components is described in chapter 2). This eight digit code should be used in conjunction with the S/T code for unique Australia-wide identification of the SLA. For non-split Localities this is the only ASGC code. For split Localities the Major SLA is the SLA which contains the greatest number of streets for the Locality.
ASGC Codes 2nd to 8th SLAs
These fields are used for Localities which are in more than one SLA. The codes for each of these SLAs comprise eight digits made up of the SD, SSD and SLA codes (each of these components is described in chapter 2). If a Locality is split all appropriate codes (up to eight) are listed against the Locality.
Major SLA Name
This is the SLA name for the ASGC code shown in the Major SLA field.
CODING TO STATISTICAL LOCAL AREA
In the diagram below, the localities labelled First Locality and Second Locality are shown bounded by dashed lines. They do not cross any S/T border.
First Locality is entirely within the boundary of SLA 1. It is not split and there will be no street records for it in the NLI Streets Sub-Index. The Localities Index record for First Locality will show one SLA code, i.e. all addresses in this Locality will have the same SLA code.
Second Locality shows a street pattern within it and one of the streets is named Split Street.
The boundary between SLA 1 and SLA 2 crosses through Second Locality and therefore this Locality is a split Locality. The NLI Localities Index shows both SLAs against the Locality record. SLA 1 will be the Major SLA as it has the largest number of streets for Second Locality.
All streets for Second Locality are contained in the Streets Sub-Index and are coded to the SLA(s) in which they lie.
The street named Split Street shown in the diagram, lies within both SLA 1 and SLA 2. It will have the relevant street number ranges recorded for each of the SLAs. Chapter 4 provides information on the Streets Sub-Index.
CHAPTER 4 STREETS SUB-INDEX
The Streets Sub-Index contains records of street data for the split Localities listed in the Localities Index. This index enables specific Statistical Local Area (SLA) coding for split Localities where the street name and number are known.
STREETS SUB-INDEX FILE FORMAT
The standard Streets Sub-Index format is a comma delimited ASCII text file with fixed length fields and a record length of 102 characters.
FIELD NAMES AND DEFINITIONS
The following field names and definitions relate to the Streets Sub-Index.
The Streets Sub-Index is subject to rules governing data representation and these are explained in Appendix 1.
Locality Name is a key field which links the split Localities on the Localities Index to their appropriate street data on the Streets Sub-Index.
Link to Localities Index
The Streets Sub-Index contains the names of all split Localities together with their street data. Each street is recorded with the State/Territory (S/T) code and four digit SLA code to which it belongs. These codes in the street data reflect the S/T code and the last four digits of one of the Australian Standard Geographical Classification (ASGC) code fields for the relevant Locality in the Localities Index. For example:
From the Localities Index, Blessington is a split Locality.
From the Streets Sub-Index the split Locality, Blessington, has street data listed.
The S/T code indicates the State or Territory in which the Locality and a street or part of a street exists. The definition of S/T is described in chapter 2.
The SLA code indicates the SLA in which the street or street segment exists. In the Streets Sub-Index only the S/T and SLA components of the ASGC code are held as this is sufficient to uniquely identify the appropriate SLA.
This field contains the names of streets, roads, avenues, etc. found within the Locality. Significant residential buildings and properties have been included for some split Localities if considered appropriate.
This field describes the Street Type that is linked to the Street Name field. Common street types have been abbreviated while lesser used ones are fully described. A full listing of the Street Types used in the NLI is detailed in Appendix 2. Where an abbreviation has been adopted for NLI purposes the full title is shown in brackets.
This field shows the geographic descriptor where it is part of the street name e.g. SMITH STREET NORTH will be represented as SMITH, ST, N.
The street directions used are:
(blank) = default
N = North
S = South
E = East
W = West
This field also shows a Multiple Occurrence flag where a street name occurs more than once in a split Locality and the streets lie in different SLAs. It flags each record of the street name.
M = Multiple Occurrence
Street Number Range
Where a street is wholly contained within an SLA the street number range is 0001-9999.
Where a street lies across an SLA boundary, a number range is displayed for the segments contained within each SLA. The number range indicates the lowest and highest numbers (inclusive) along the street for which each SLA code is valid.
Where a street crosses SLA boundaries and the street number range is unknown or, in the case of many rural roads, does not exist or cannot be determined from current sources, then the value of 0000-0000 is given for the street number range.
This field flags whether all or specifically odd or even street numbers are included in the street’s number range for the SLA code.
O = odd numbers only
E = even numbers only
A = all numbers
Where a street is entirely within an SLA, the street number range is represented 0001-9999 A.
Where the odd side of a street is wholly within an SLA, the street number range is represented 0001-9999 O.
Where the even side of a street is wholly within an SLA, the street number range is represented 0002-9998 E.
Where the number range on the odd side of the street within an SLA is unknown, ambiguous, or does not exist, the street number range is represented as 0000-0000 O.
Where the number range on the even side of the street within an SLA is unknown, ambiguous, or does not exist, the street number range is represented 0000-0000 E.
Where the number range on both the odd and even sides of the street within an SLA is unknown, ambiguous, or does not exist, the street number range is represented 0000-0000 A.
APPENDIX 1 OTHER RULES GOVERNING DATA REPRESENTATION IN THE NLI
The NLI aims to assist users to code addresses to the relevant Australian Standard Geographical Classification (ASGC) Main Structure code. The many source materials which contribute to the Localities Index and Streets Sub-Index often represent Locality and Street data with a variety of spellings, punctuations and abbreviations.
Chapters 3 and 4 in this document describe what is recorded in each of the fields of the Localities Index and the Streets Sub-Index files. Other rules governing how source material should be represented are also applied to provide consistency in the NLI and these are set out below.
Rules applied to the Locality Name field:
All Locality Names are in capital letters;
No punctuation is used;
An abbreviation, ST, is used to represent the word SAINT where it is the first part of a Locality Name. At all other times it is shown as a full spelling;
The words MOUNT, PORT and POINT are not abbreviated;
The abbreviations RAAF and RAN are used for Locality Names involving Royal Australian Air Force or Royal Australian Navy bases;
Locality Name qualifiers such as North, South, Lake, Island and the like are not abbreviated; and
The Property Indicator field shows the P flag for Locality Names which in source materials are described as agricultural properties. Descriptors like Station, Homestead or Property are not used in agricultural property names.
Rules applied to the ASGC codes and the Major SLA name fields:
All ASGC codes used in the NLI are consistent with the relevant edition of the ASGC;
All Major SLA names include punctuations, abbreviations, and spellings which are consistent with the relevant edition of the ASGC; and
The Major SLA name is in capital letters.
Rules applied to the Locality Name field:
Data are consistent with the Localities Index Locality Name field.
Rules applied to the ASGC code field:
The ASGC codes for State/Territory and SLA for each Street record are displayed. They are consistent with the relevant edition of the ASGC and the codes for the corresponding Locality Name in the Localities Index.
Rules applied to the Street Name field:
The punctuation, abbreviation and word treatment rules applied to the Locality Name field also apply to the Street Name field;
In the case of streets such as 'The Parade', 'The Esplanade', etc. the whole name is included in the Street Name field. The whole name is also included in the Street Name field in the case of streets such as 'The Avenue of Honour', where the street type does not occur at the end of the street name (ignoring the street direction if it is present). In both cases the Street Type field is left blank.
The NLI aims to have an exhaustive listing of the street patterning for a split Locality. There are also other features that are included in the NLI Streets file; these are not exhaustively recorded, but are added ‘subjectively’ and include:
Rules applied to the Street Type field:
The Street Type field shows the P flag for features of a split Locality which in source materials include descriptors like Station, Homestead or Property. Those descriptors are not displayed in the Street Name field.
Street Type 'BLDG' is used to indicate a feature that is neither a street or a property. In most cases these will be buildings in the everyday sense, but it is also applied to features such as Airports and University Campuses which would not normally be considered buildings.
In the case of streets such as 'The Parade', 'The Esplanade', etc. the Street Type field is left blank. The Street Type field is also left blank in cases where the street type does not occur at the end of the street name (ignoring the street direction if it is present), for example 'The Avenue of Honour'. In both cases the whole name is included in the Street Name field.
For a listing of valid Street Types used in the NLI see Appendix 2.
APPENDIX 2 STREET TYPES USED IN THE NLI