EXPLANATORY NOTES


INTRODUCTION

1 This quarterly publication contains data from both ABS and non-ABS sources. The ABS publications referenced within the publication, as well as the websites of non-ABS organisations, can be found listed below. For further information, users are directed to these references.


AIR QUALITY

2 The Environment Protection Authority (EPA) reports air quality as an index for any given pollutant as its concentration expressed as a percentage of the relevant standard. It enables easy interpretation of whether the pollutant is at a level which may cause harm. An index value of 100 means the pollutant is currently at a concentration equal to the National Environment Protection Measure (Air NEPM) or State Environment Protection Policy (The Air Environment) (SEPP) standard levels (levels designed to protect human health and the environment). Indexes are calculated separately for each measured pollutant: Ozone, Nitrogen Dioxide, Sulfur Dioxide, Carbon Monoxide, Fine Particulates (PM10), Visibility (Airborne Particle Index). For each station, the daily pollutant indexes are the maximum index values for that day. Note that not all pollutants are measured at each station. The EPA also calculates an overall Air Quality Index, which amalgamates each pollutant index into an overall measure of air quality at each station.

3 The air quality data have been provided for the Ozone and Visibility (or Airborne Particle) Indexes as these are the dominant pollutants and are widely measured across the EPA network. It should also be noted that meteorological conditions are a major determinant on the incidence of elevated pollutant levels. Hence significant daily, seasonal and annual variations can be expected in air quality. For more information on air quality, see the EPA web site.

4 The air quality index is converted into a qualitative scale with five commonly understood terms. Very good (0-33), Good (34-66) and Fair (67-99) represent measurements within the standards, while Poor (100-149) and Very poor (150+) represent measurements exceeding the standards.

5 For air quality reporting purposes the Port Phillip Region (PPR) has been divided into 4 regions: East, West, City and Geelong. Air monitoring stations assigned to each region are: East - Alphington, Brighton, Box Hill, Dandenong, Mooroolbark; City - RMIT, Richmond; West - Footscray, Melton, Point Cook, Paisley; Geelong - Point Henry, Geelong South. In addition, the Latrobe Valley has stations at Moe and Traralgon. The regional index is considered to be the maximum of the station indexes calculated within each particular region. The daily index reported for a region is the maximum region index recorded each day.


CHANGES IN CAPACITY OF WATER STORAGES

6 The capacity at full service level of Victoria's water storages changes periodically due to a number of factors including the commissioning and decommissioning of reservoirs, and the review of operational storage capacities of reservoirs. A summary of changes affecting capacity at full service level is given below.

• December 2004: Capacity of storages in Werribee and Maribyrnong basins reduced by 7 GL;
• April 2005: Capacity of Glenelg/Wimmera basin storages reduced by 24 GL;
• January 2007: Moondarra Reservoir (capacity 30 GL, initial storage volume 23 GL) added to the Thomson/Latrobe basin;
• September 2008: Glenmaggie Reservoir (Thomson/Latrobe basin) capacity reduced by 12 GL;
• April 2009: Lake Mokoan (Broken basin, capacity 365 GL) decommissioned;
• June 2009: Tarago Reservoir (capacity 38 GL, initial storage volume 22 GL) added to the Melbourne supply system.

MELBOURNE METROPOLITAN AREA

7 Most of the small area data provided by non-ABS organisations are aggregates at Local Government Area (LGA) level. With one exception, LGAs do not cross Statistical Division (SD) boundaries, and therefore it is generally possible to form SD data from aggregate LGA data. However, while the majority of the Yarra Ranges (S) LGA is in the Melbourne SD, the Yarra Ranges (S) - Pt B SLA is in the Gippsland SD. As a result, in these instances it is not possible to derive data for Melbourne and Gippsland SDs as exactly defined in the Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0).

8 Where necessary, the Yarra Ranges (S) LGA as a whole is included with the LGAs in Melbourne SD to form a region referred to as the Melbourne Metropolitan Area (MMA). Consequently, in these instances Gippsland SD excludes Yarra Ranges (S) - Pt B SLA.

9 As an indication of the relative size of Yarra Ranges (S) - Pt B SLA, at 30 June 2008 it had a preliminary estimated resident population (ERP) of 612 persons. At the same date, the total ERP of Yarra Ranges (S) LGA was 146,886, while Gippsland SD had a total ERP of 170,779.


GEOGRAPHY AND MAPS

10 Maps of SLAs and SDs within Victoria can be found in Australian Standard Geographical Classification (ASGC) (cat. no. 1216.0) on the Downloads page (1216.0 - 2009 ASGC - Victorian Maps). A listing of SLAs within each LGA (Local Government Areas and Statistical Local Areas - Alphabetic) can be accessed from the same page, along with listings of SLAs within each SD (Main Structure - Detailed) and Statistical Region (SR) (Statistical Region Structure - Detailed).

11 Unless otherwise indicated, boundaries of LGAs, SDs and SRs referred to in this publication are consistent with those in the 2009 Edition of the ASGC. The most recent change to an LGA boundary in Victoria was effective from 1 July 2008 and involved Melbourne (C) gaining 111.8 hectares (and 5,712 persons based on preliminary ERP at 30 June 2008) from Moonee Valley (C).


Regional and small area labour force estimates

12 The regions in Victoria for which the ABS produces estimates from the Labour Force Survey are revised at the time of the labour force sample redesign following each Census of Population and Housing and remain stable until the next labour force sample redesign. From November 2007, these regions are consistent with the SRs in the 2006 Edition of the ASGC. Consequently, the LGA boundary change between Melbourne (C) and Moonee Valley (C) is not reflected in LFS data. There were no changes to Victorian SR boundaries between 2001 and 2006 that involved population. For further information on LFS data at regional level, please see Information Paper: Regional Labour Force Statistics (cat. no. 6262.0). Maps of SRs used in the LFS can be found in Australian Labour Market Statistics, Jul 2009 (cat. no. 6105.0) on the Downloads page (6105.0 - Labour Force Region Maps - Victoria - 2007).

13 The quarterly small area unemployment rate estimates produced by DEEWR are based on the regions used by the ABS in the LFS. Even though there were no changes to Victorian SR boundaries between 2001 and 2006, there have been changes to LGA boundaries involving population which may have impacted on the small area unemployment rate time series. These boundary changes have been incorporated into the estimates for the smoothed series (the series included in this publication) from September quarter 2008, and have not been backcast to earlier periods. In Victoria, the affected LGAs are:

• Alpine (S) - previously included Falls Creek and Mount Hotham Alpine Resorts (estimated resident population of 163 at 30 June 2003);
• Benalla (RC) - previously part of Delatite (S);
• Mansfield (S) - previously part of Delatite (S); and
• Unincorporated Vic. - previously only French Island, now includes Falls Creek, Mount Baw Baw, Mount Buller and Mount Hotham Alpine Resorts.

14 Changes to internal SLA boundaries between 2001 and 2006 have affected the timing of the introduction of new LFS population benchmarks based on the 2006 Census of Population and Housing into the small area unemployment rate time series for the LGAs of Baw Baw (S), Campaspe (S), Colac-Otway (S), Greater Bendigo (C), Knox (C), Whittlesea (C) and Yarra Ranges (S). For these LGAs, the new benchmarks have been incorporated from September quarter 2008, which is two quarters later than other LGAs. The new benchmarks for Alpine (S) and Unincorporated Vic. have also been introduced from September quarter 2008.

15 The boundary changes to geographic areas and new population benchmarks described above were first introduced into the small area unemployment rate time series in March quarter 2009, with data for previous periods being revised back to either March quarter 2008 or September quarter 2008 (depending on the nature of revisions required, as described above).


Tourism Regions

16 Tourism Regions are defined by relevant state/territory tourism organisations and represent groups of SLAs. Each year, any changes to Tourism Regions (including SLA boundary changes incorporated in the current edition of the ASGC) are applied from the first reference period of the Survey of Tourist Accommodation in the following calendar year (i.e. the March quarter). For a map of Victorian Tourism Regions, and a listing of SLAs within each Tourism Region, please see Tourism Region Maps and Concordance Files, Australia (cat. no. 9503.0.55.001).


Thematic maps

17 This publication contains maps illustrating selected characteristics relating to the population in LGAs.

18 For each map, five class intervals, each with a different colour shade, have been used to help interpret the distribution of the characteristic being mapped. LGAs with similar values are grouped in the same class, and the number of LGAs in each class will vary depending on the distribution of the population being mapped.

19 Each map contains a legend showing the colour and values for each class of the mapped data. For simplicity, the ranges are shown as, for example, '9.7-16.3' and '16.3-23.0'. These should be read as 'from 9.7 to less than 16.3' and 'from 16.3 to less than 23.0'. Individual values appear in one range only.


ABS PUBLICATIONS

20 The following ABS publications are referenced in this release of State and Regional Indicators, Victoria:

• Retail Trade, Australia (cat. no. 8501.0)
• Labour Price Index, Australia (cat. no. 6345.0)
• Sales of New Motor Vehicles, Australia (cat. no. 9314.0)
• Australian Demographic Statistics (cat. no. 3101.0)
• Births, Australia (cat. no. 3301.0)
• Deaths, Australia (cat. no. 3302.0)
• Labour Force, Australia (cat. no. 6202.0)
• Labour Force, Australia, Detailed - Electronic Delivery (cat. no. 6291.0.55.001)
• Labour Force, Australia, Detailed, Quarterly (cat. no. 6291.0.55.003)
• Average Weekly Earnings, Australia (cat. no. 6302.0)
• Estimates of Personal Income for Small Areas, Time Series, 2003-04 to 2006-07 (cat. no. 6524.0.55.002)
• Australian National Accounts: National Income, Expenditure and Product (cat. no. 5206.0)
• Consumer Price Index, Australia (cat. no. 6401.0)
• House Price Indexes: Eight Capital Cities (cat. no. 6416.0)
• Building Activity, Australia (cat. no. 8752.0)
• Building Approvals, Australia (cat. no. 8731.0)
• Engineering Construction Activity, Australia (cat. no. 8762.0)
• Tourist Accommodation, Small Area Data, Victoria (cat. no. 8635.2.55.001)
• Livestock Products, Australia (cat. no. 7215.0)
• Livestock and Meat, Australia (cat. no. 7218.0.55.001)
• International Trade in Goods and Services, Australia (cat. no. 5368.0)

NON-ABS WEBSITES

21 The websites of the following organisations may provide further information on some of the data provided in this release of State and Regional Indicators, Victoria:

• Department of Education, Employment and Workplace Relations (DEEWR)
• Dairy Australia
• Environment Protection Authority, Victoria
• Department of Sustainability and Environment, Victoria