3222.6 - Population Projections, Tasmania, 1999 to 2021
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 10/10/2001
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About these Projections
Note: The same fertility, mortality and overseas net migration assumptions were used in all series. C. Assumptions C.1 Summary Base population: the base population for the projections was the preliminary estimated resident population at 30 June 2000. Fertility: One assumption is made. The total fertility rate declines from 1.84 babies per woman in 2000 to 1.67 babies per woman in 2007-08, and then remains constant. Mortality: One assumption is made. The 1986-1996 rate of improvement in life expectancy, which continues for the next five years and then gradually declines, results in life expectancy at birth of 80.1 years for males and 84.0 years for females in 2021. Overseas migration: One assumption is made. Annual net overseas migration gain of 129 from 2001-02. Interstate migration: Three assumptions are made - 1 Annual net interstate migration loss of 500 persons. 2 Annual net interstate migration loss of 1,500 persons. 3 Annual net interstate migration loss of 2,500 persons. C.2 Fertility Summary There is one long-term fertility assumption. This assumption is based on the fact that the decline in the total fertility rate (TFR) will continue and result in a TFR of 1.67 babies per woman in 2007-08. It then remains constant to the end of the projection period. Trends in the total fertility rate Before the end of the baby boom in Tasmania in the mid-1960s, the TFR reached its highest level in 1961 at 3.5 babies per woman. It fell in the following years, initially slowly but then rapidly in the early 1970s. Below replacement level fertility (2.1 babies per woman) was reached in 1976. In the 1990s, fertility declined further. Assumed total fertility rates Given the current trends in Tasmania's fertility only one assumption was proposed for the future total fertility rate. It is proposed that by 2008 the TFR will drop to 1.67 and then remain constant till the end of the projection period. Since the late 1970s, Tasmania's TFR has fluctuated between 1.8 and 2.0 babies per woman. Despite the small falls in the 1990s, it is reasonable to assume that the declines in the TFR over the last 10 years will continue over the next 10 years to around 1.67 babies per woman. This assumption is consistent with factors that are considered associated with lowering of fertility, such as increased participation of women in education and in the labour force. These higher participation rates may result in smaller families and increasing childlessness, both of which would lower the TFR. C.3 Mortality One assumption was made at the Tasmanian level. The assumption is that life expectancy at birth increases from the 1996-1998 level of 75.2 years for males and 80.6 years for females to 80.1 years for males and 84.0 years for females by 30 June 2021. It is based on the Australian average annual rate of improvement in life expectancy from 1986-1996 of 0.30 years per year for males and 0.22 years per year for females continuing from 1999 to 2003 and then gradually slowing. The pattern of change in Australian age-specific death rates from 1970-1972 to 1995-1997 has been assumed to continue for the projection period. This has been applied to base age-sex mortality rates taken from 1996-1998 Tasmanian life tables. Where the trend from 1970-1972 to 1995-1997 showed an increase in age-specific death rates (e.g. males aged 30-34 years), some arbitrary adjustment was performed to prevent the age-specific death rates from increasing in the future. Further adjustments were made to the assumed rates of change in age-specific death rates to conform to the predetermined life expectancies at birth for future years. C.4 Overseas Migration Assumption The long-term assumed level of net overseas migration is about 130. This is based on the Tasmanian share of Australian net overseas migration during the three-year period 1996-97 to 1998-99. The proportion of migrants going to Greater Hobart SD and the balance of Tasmania was based on the average distribution of migrants arriving in 1990-91 and 1995-96, according to the 1991 and 1996 Censuses respectively. This distribution remains constant throughout the projection period. Assumed future age-sex profile of overseas migrants The assumed age-sex structure of each migration component (permanent and long-term) for Tasmania was based on the average structure from 1996-97 to 1998-99. Age-sex profiles at the part of State level were derived from the 1996 Census question on residence one year ago. Overseas departures are assumed to have the same age-sex distribution as overseas arrivals. These distributions were constrained to Tasmanian overseas arrivals and departures data for 1995-96. C.5 Interstate Migration Assumptions Because of the volatility of net interstate migration flows, three long-term assumptions are made. For Tasmania these assumptions provide high, medium and low levels of losses due to interstate migration. The medium assumption is based on averages for the last three decades, with more weight given to the past 10 years. The high and low assumptions reflect the variability in the historical data, and give a plausible broad range of projection outcomes. They also reflect the net interstate migration levels experienced during 1997-98 and 1998-99. Trends Interstate migration is the most volatile component of population change for Tasmania. Therefore this movement of people between regions is an important determinant of Tasmania's population distribution. Apart from a distinct pattern of net flows to warmer climates, the levels of interstate migration are sensitive to the differences between State and Territory economies and the number of permanent and long-term overseas arrivals. Over recent years, Tasmanian interstate migration patterns have been dominated by a northward stream on the east coast with a smaller stream to the west coast. These streams result in net gains for all mainland States and Territories. The average annual net gain to Queensland over the past decade has been about 1,300 people, 500 to Victoria, 300 to Western Australia, 100 to New South Wales, 100 to the ACT and negligible gains to South Australia and the Northern Territory. Assumed interstate migration Tasmania has experienced net losses in most years since 1971-72. Since 1991-92, increasing net losses have been recorded due to an increase in departures. Queensland initially received the majority of departures but in 1997-98 were replaced by Victoria. Tasmanian net interstate migration losses in that year reached almost 4,000, the highest loss experienced by Tasmania since World War II. The preliminary estimates for 1999-2000 indicate a slightly smaller net loss of just under 3,000. The levels of assumed net interstate migration for the 1999-2021 projections have been derived by analysing the trends during the past two decades. Three alternative assumptions are made to allow for a variety of scenarios for interstate migration levels across Tasmania. Assumption 1 assumes an annual net loss of 500 persons, assumption 2 assumes an annual net loss of 1,500 persons and assumption 3 assumes an annual net loss of 2,500. Overall, the medium assumption most closely reflects the long-term average net interstate migration experience of Tasmania. The high and low levels attempt to cover a range of net interstate movements. Each assumption remains constant after a transitional period from 1999-2000 to 2002-2003. These assumptions should be interpreted as average annual levels of net interstate migration and not as actual levels. Assumed capital city and balance of State migration The interstate migration assumptions for Greater Hobart Statistical Division and the balance of Tasmania are based on historical trends. Net total migration to Greater Hobart Statistical Division and the balance of Tasmania is assumed to be the difference between population growth and natural increase in these regions. Net interstate migration is assumed to be the difference between net total migration and net overseas migration. D. Nature of projections The nature of the projection method and inherent fluctuations in population dynamics mean that care should be taken when using and interpreting the projection results. The projections are not exact forecasts but simply illustrate future changes which would occur if the stated assumptions were to apply over the projection period. In addition to the assumptions described above for fertility, mortality and overseas and internal migration, the projections accommodate all known planned developments. The projections do not attempt to allow for non-demographic factors (eg. major government policy decisions, economic factors, catastrophes, wars) which may affect future demographic behaviour. The unpredictability of migration trends, especially in the short-term, can have a significant effect on projection results. Special care should be taken with small SLAs (populations under 1,000 people) and small age-sex cells (populations under 100 people). All SLAs in these projections are based on the Australian Standard Geographic Classification boundaries as they existed at 1 July 2000 (ASGC 2000). The actual boundaries for a given SLA, or for other geographic regions such as Local Government Areas (LGAs) derived from these SLAs, may change over time making the projections not comparable in the future with other data. E. Liability It is important to recognise that the projection results given in this report simply reflect the assumptions made about future fertility, mortality and migration trends. While the assumptions are formulated on the basis of an objective assessment of past demographic trends and their likely future dynamics, there can be no certainty that they will be realised. No liability will be accepted by the Australian Bureau of Statistics for any damages arising from decisions or actions based upon these population projections. F. Referencing these statistics Source: Australian Bureau of Statistics. Population Projections, Tasmania, 1999-2021 (ABS Cat. no. 3222.6). G. Additional information For further information on population projections refer to the ABS publication Population Projections, Australia, 1999 to 2101 (Cat. no. 3222.0) available from ABS offices in all capital cities. For more information, or quotes on the preparation of alternative projections, please contact: Matthew Berger Demography Section Australian Bureau of Statistics Tel. 02 6252 6639 Email: matthew.berger@abs.gov.au Document Selection These documents will be presented in a new window.
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