EXPLANATORY NOTES
INTRODUCTION
1 This publication contains statistics relating to overseas migration, interstate migration and estimated resident population (ERP) by country of birth. This includes components of net overseas migration (NOM) that is, permanent and long-term arrivals, permanent and long-term departures and migration adjustments, the number of settler arrivals by visa eligibility category as well as contextual information such as international migration statistics of other countries.
NET OVERSEAS MIGRATION
2 As a legislative obligation, the ABS is required to provide a preliminary ERP for each December quarter by early June of the following year. The Australian Government uses ERP to distribute funds across all states and territories, and to develop a wide range of government policies. As a component of ERP, the ABS publishes two sets of NOM estimates, preliminary and revised. Since revised estimates can only be calculated 15 months after a reference quarter, preliminary estimates are calculated to meet immediate requirements.
3 NOM figures are based on net permanent and long-term overseas movements. Movements of less than twelve months (short-term movements) are excluded from the calculation of NOM.
Category jumping
4 Many overseas travellers travel for shorter or longer periods than they intend, as recorded on their passenger cards (See Appendix 1: Passenger Cards). NOM estimates from July 1982 until June 1997 include an adjustment for the net effect of category jumping. Category jumping is a measure of the discrepancy between movements recorded as short-term, long-term or permanent at the time of movement, and the category of movement recorded at the completion of a journey. Twelve months after a reference year it can be determined whether the number of initially-recorded short-term, long-term and permanent arrivals and departures match actual patterns of movement.
5 For example, some visitors arriving may state that their intention is to stay in Australia for more than twelve months. However, they may change their travel plans and depart the country after an actual duration of only six months. Since migration figures are affected by this change in travel behaviour, an adjustment is incorporated into the NOM estimate and ERP.
6 The method used to estimate category jumping up until June 1997 inclusive was based on aggregate flows of traveller movements rather than individual travellers. As well, until June 1998 the measurement of duration of stay or absence on the second leg of travel was based on passenger reporting on the arrival or departure card. This self reported duration was used to determine the time at which a person arrived (for visitors) or left Australia (for Australian residents). However, from July 1998 onwards, implementation of a new passenger card design and processing system enabled the Department of Immigration and Citizenship (DIAC) to derive actual duration of stay or absence by matching both arrival and departure cards rather than relying on passengers reporting their duration of stay or absence.
Matching traveller movements
7 Despite this improvement in the quality of actual duration of stay or absence data, the above estimation method appeared incapable of producing acceptable estimates of category jumping. Given that category jumping constituted only a small fraction of ERP and that estimates produced by the above method seemed highly volatile, the ABS decided to set category jumping estimates to zero from September quarter 1997 onwards until a better estimation technique was developed.
8 Through the provision of additional data from DIAC, the ABS now has the ability to match traveller movements over time. This enables a movement history to be constructed for those arriving and departing and thus calculate an actual duration of stay.
9 Matching traveller movements has enabled the adjustment of permanent and long-term movement. This adjustment (termed 'migration adjustment') allows for components of NOM to be presented on an adjusted basis.
Adjustment and revision status of components of NOM - summary
10 For more information on category jumping and the interim method of adjusting NOM, see Demography Working Paper 2003/5 - Net Overseas Migration: Adjusting for Actual Duration of Stay or Absence (cat. no. 3137.0). This paper is available on the ABS web site, <www.abs.gov.au>. For further details on revisions to NOM, see the Technical Note in this publication and an expanded note in Australian Demographic Statistics (cat. no. 3101.0).
- 1996-97 and before: Category jumping for NOM only available; not available for components of NOM;
- 1997-98 to 2000-01: Category jumping set to zero;
- 2001-02, 2002-03, 2003-04 and 2004-05: Components have been adjusted on a revised basis. Data is presented in this publication on this basis except where indicated;
- 2005-06, long-term visitor arrivals, long-term resident departures: Have been adjusted. Data is presented in this publication on this basis except where indicated;
- 2005-06, permanent movement: Has not yet been adjusted, as permanent movement is not adjusted on a preliminary basis, and components have not yet been adjusted on a revised basis for 2005-06.
Review of method for adjusting overseas migration
11 The method for estimating NOM has been reviewed in response to problems with estimation of category jumping. The review also addressed the changing patterns of travel into and out of Australia, in particular the increased propensity for travellers to interrupt longer periods of stay or absence. For further information see
Information Paper: Statistical Implications of Improved Methods for Estimating Net Overseas Migration, Australia, 2006 (cat. no. 3107.0.55.005), to be released on 26 April 2007.
12 The improved method for estimating NOM will be implemented in ABS population estimates in June 2007 with the release of the December quarter 2006 issue of Australian Demographic Statistics (cat. no. 3101.0). For further information relating to the improved method for estimating NOM, or the implementation of this method, please contact Patrick Corr on Canberra (02) 6252 6411, email <patrick.corr@abs.gov.au>.
Permanent residency grants
13 A number of people arriving temporarily in Australia are subsequently granted permanent residency. These permanent residency grants contribute to meeting the Australian Government's immigration targets but may be unrelated to stated intentions to stay in Australia on arrival at an earlier date. Accordingly, they are not included in unadjusted permanent arrivals in this publication, as they did not arrive in Australia on a permanent basis. The proportions of migration adjustment which were due to short-term and long-term visitor arrivals gaining on-shore grants of permanent residency is not known.
14 For more information on permanent additions to the population see the DIAC publication Immigration Update, available on the DIAC web site, <http://www.immi.gov.au>.
NET INTERSTATE MIGRATION
15 Information about internal migration is available from population censuses, sample surveys of internal movements and administrative by-product data such as Medicare change of address information.
- Prior to June 1986, quarterly estimates were derived from records of interstate changes of addresses advised to the Department of Social Security in connection with family allowance payments. Family allowance transfer data related to children only, and interstate migration for all ages was based on the expansion of these family allowance data using ratios of adult to child populations. These ratios, calculated for each interstate flow, were based on results from the latest available census. Data from the Internal Migration Survey were used to constrain total interstate moves to those revealed by the survey. Data derived from the ratio expansion method were subject to revision in the light of the more accurate census data.
- Since June 1986, estimates of interstate migration have been derived using confidentialised information on interstate changes of address supplied by Medicare Australia (formerly the Health Insurance Commission) in the process of administering Medicare. Prior to June 1996, only Medicare transfers for persons aged 1-14 years were used, as most other ages suffered from significant under-registration of transfers. The method used to expand the 1-14-year-old movers was similar to the previous method, with adult to child expansion ratios based on information from the latest available census being applied to the Medicare movers data for ages 1-14 years for each interstate flow.
- Since June 1996, the method used to estimate interstate migration was revised after investigations identified that coverage of Medicare had improved, and become more stable for those ages which still suffered from significant under-registration. Movers of each age are now used to directly estimate interstate migration for the same age. Estimates are then adjusted for undercoverage by Medicare for those ages which still have significant under-registration (i.e. males aged 16-29 years and females aged 18-24 years) by comparing census and Medicare data. This method also represents an improvement over the previous methods as it produces an age profile on interstate movers. In recent years an adjustment for defence force movements has been included.
16 For more information on the method of estimating net interstate migration, see Demography Working Paper: 2004/1, Review of Interstate Migration Method (cat. no. 3106.0.55.001) and Information Paper: Evaluation of Administrative Data Sources for Use in Quarterly Estimation of Interstate Migration, 2006 to 2011 (cat. no. 3127.0.55.001). These papers are available on the ABS web site <https://www.abs.gov.au>.
OVERSEAS ARRIVALS AND DEPARTURES
Source of statistics
17 Persons arriving in, or departing from, Australia provide information in the form of incoming and outgoing passenger cards (see Appendix 1). Incoming persons also provide information in visa applications, apart from people travelling as Australian or New Zealand citizens. This and other information available to DIAC serve as a source for statistics on overseas arrivals and departures.
18 Implementation of the Migration Reform Act 1992 (Cwlth) by DIAC required that a health and character check be incorporated with the Incoming Passenger Card. A redesign of both passenger cards followed and new passenger cards were officially introduced on 1 September 1994 with minor alterations to the cards in March 1995.
19 In July 1998 DIAC revised the incoming and outgoing passenger cards and associated procedures as well as computer systems. As a result of these changes, some questions on the passenger cards are not compulsory and answers to these questions are not checked by Customs officers. For more information see the May 1998 issue of Overseas Arrivals and Departures, Australia (cat. no. 3401.0). Since July 1998 there have been additional minor changes to both passenger cards.
Scope and coverage
20 All permanent movements and all movements with a duration of stay of one year or more are completely enumerated.
21 The statistics exclude the movements of operational air crew and ships' crew, of transit passengers who pass through Australia but are not cleared for entry, and of passengers on pleasure cruises commencing and finishing in Australia, and unauthorised arrivals.
ESTIMATED RESIDENT POPULATION
Source of statistics
22 Australia's population estimates for the period since 1971 are compiled according to the place of usual residence of the population. An explanation of the conceptual basis for population estimates is given in Information Paper: Demographic Estimates and Projections: Concepts, Sources and Methods (cat. no. 3228.0), available on the ABS web site, <https://www.abs.gov.au>.
Method of estimation
23 The estimated resident population is an estimate of the Australian population obtained by adding to the estimated population at the beginning of each period the components of natural increase (on a usual residence basis) and net overseas migration. For the states and territories, account is also taken of estimated interstate movements involving a change of usual residence. Estimates of the resident population are based on census counts by place of usual residence, to which are added the estimated net census undercount and Australian residents estimated to have been temporarily overseas at the time of the census. Overseas visitors in Australia are excluded from this calculation.
24 After each census, estimates for the preceding intercensal period are revised by incorporating an additional adjustment (intercensal discrepancy) to ensure that the total intercensal increase agrees with the difference between the ERPs at the two 30 June dates in the respective census years.
Natural increase
25 Natural increase is the excess of births over deaths. For the compilation of population estimates, births and deaths by state or territory of usual residence are used. For preliminary population estimates, births and deaths by quarter of registration are used as a proxy for quarter of occurrence, but for revised and final estimates, year and quarter of occurrence data are used to ensure the accuracy of single year of age population estimates.
Birthplace
26 Estimated resident population by age and sex is calculated by country of birth for 30 June of each year by taking into account births, deaths and NOM over the preceding twelve months. All births in this period are added to the Australia-born population. Deaths during the period are subtracted from the population of the preceding year on the basis of financial year of birth, sex and country of birth. NOM is added to that population on the same basis.
27 For 2002-03 to 2005-06 NOM was disaggregated on the basis of the countries of birth of permanent arrivals and departures data, instead of using country of birth of all movements. This was done because the inclusion of long-term movements in the calculation of NOM by birthplace yielded anomalous results in country of birth disaggregation.
COUNTRY CLASSIFICATION
28 The classification of countries used throughout this publication is the Standard Australian Classification of Countries (SACC), 1998 (cat. no. 1269.0). This replaced the Australian Standard Classification of Countries for Social Statistics (ASCCSS) used in earlier issues of this publication.
29 Statistics on country of birth, citizenship, residence or main destination have certain limitations because of inadequate reporting on passenger cards. For instance, it is not possible to accurately identify separately England, Scotland and Wales. The United States of America includes 'America (undefined)'.
STATE AND TERRITORY CLASSIFICATION
30 Following the 1992 amendment to the Acts Interpretation Act to include the Indian Ocean territories of Christmas Island and the Cocos (Keeling) Islands as part of geographic Australia, population estimates commencing with the September quarter 1993 include estimates for these two territories. To reflect this change, another category of the state and territory classification was created, known as Other Territories. Other Territories includes Jervis Bay Territory and Christmas Island and the Cocos (Keeling) Islands. Where information is presented by state and territory, information for Other Territories is not presented separately but is included in Australia totals.
ACKNOWLEDGMENT
31 ABS publications draw extensively on information provided freely by individuals, businesses, governments and other organisations. Their continued cooperation is very much appreciated; without it, the wide range of statistics published by the ABS would not be available. Information received by the ABS is treated in strict confidence as required by the Census and Statistics Act 1905.
RELATED PUBLICATIONS
32 Users may also wish to refer to the following ABS publications:
- Australian Demographic Statistics (cat. no. 3101.0) - issued quarterly;
- Overseas Arrivals and Departures, Australia (cat. no. 3401.0) - issued monthly;
- Demography Working Papers, ABS web site, <https://www.abs.gov.au>;
- Information Paper: Demographic Estimates and Projections: Concepts, Sources and Methods (cat. no. 3228.0), ABS web site, <https://www.abs.gov.au>;
- Census of Population and Housing: Australia in Profile - A Regional Analysis, 2001 (cat. no. 2032.0);
- Census of Population and Housing: Population Growth and Distribution, 2001 (cat. no. 2035.0).
33 Related statistics are also published by DIAC, available on the department's web site <http://www.immi.gov.au>:
- Immigration Update;
- Population Flows - Immigration Aspects;
- Settler Arrivals.
34 In July 2005, publication data released on the ABS web site were made available free. Users can now access the full range of electronic ABS data free of charge on <www.abs.gov.au>. Improving the availability of official statistics to all Australians means everyone can now download all ABS data on this web site without charge.
35 Current publications and other products released by the ABS are listed in the Catalogue of Publications and Products (cat. no. 1101.0). The Catalogue is available from any ABS office or the ABS web site <https://www.abs.gov.au>. The ABS also issues a daily Release Advice on the web site which details products to be released in the week ahead.
36 As well as the statistics included in this and related publications, additional demographic information is available on the ABS web site, <https://www.abs.gov.au>; click Themes, then under People click on Demography.
UNPUBLISHED STATISTICS
37 The ABS can make available information that is not published. Generally, a charge is made for providing this information. Inquiries should be made to the National Information and Referral Service on 1300 135 070.
38 The following variables are available for overseas arrival and departure data:
- Country of citizenship (nationality)
- Country of birth
- Age
- Sex
- Marital status (not available for Australian and New Zealand citizens)
- Category of travel
- Country of embarkation/disembarkation
- Airport/port of arrival/departure
- Arrival/departure date
- Permanent migrants:
- Previous/future country of residence
- State or territory of intended address/lived
- Overseas visitors:
- Intended/actual length of stay
- Main reason for journey
- Country of residence
- State or territory of intended address/in which most time was spent
- Australian residents:
- Intended/actual time away from Australia
- Main reason for journey
- Country spent/intend to spend most time abroad
- State or territory of intended address/state or territory of residence
- Intention to live in Australia for next twelve months
39 The following variables are available for ERP by country of birth:
- Country of birth: 236 countries
- Age: five-year age groups
- Sex
- State/territory of usual residence: census years only