Estimating the components of indigenous population change, 1996–2001

Every five years, the national Census of Population and Housing provides a window on the demographic, social and economic characteristics of Australia’s Indigenous population. Of particular interest to demographers is the opportunity that this provides to benchmark intercensal population estimates and to estimate the components of intercensal population change. In line with each census count of Indigenous Australians since 1971, when a question on self-identified Indigenous origins was introduced, the 2001 count produced an intercensal change in numbers that cannot be explained by demographic processes alone. Unpredictability thus remains a hallmark of Indigenous population growth. In accounting for the unexplained component of population growth we refer to changes in census coverage rather than specifically to changes in propensity to identify. The former may include the latter, although to what extent is unknown. In truth, we still cannot determine the factors that contribute to non-demographic population growth, although it is possible to speculate. There is evidence of a highly systematic movement of people into the census-identified Indigenous population in 1996, and out of the population in 2001. This is suggestive of procedural or processing change, as much as anything else. A striking feature of the 2001 Census analysis is that Indigenous women’s fertility has reached, or may even now be below, replacement level, confirming the findings from recent ABS analysis of births registration data. Aside from the momentum for growth already built into the Indigenous age structure, and any further increased identification, it is therefore only the contribution made by Indigenous births to non-Indigenous women that will now sustain Indigenous population growth. Of particular note is a substantial decline in Indigenous teenage fertility. Even if this is independent of any rise in economic participation, it nonetheless reduces one of the barriers to participation and, if it continued, would lead to further downward pressure on fertility. At the same time, Indigenous fertility levels vary regionally, with high levels still reported in many remote regions. By contrast, the continued lack of convergence between Indigenous and non-Indigenous mortality rates is striking. The census provides confirmation of mortality estimates from vital registration data and reveals that life expectancy for Indigenous males at 57 years has not changed since 1996, while female life expectancy has only slightly improved to 65 years. Both indicators remain way behind the rest of the Australian population. Comparison is also made with life expectancies among select South Pacific populations; only Papua New Guinea reports life expectancies below those observed among Indigenous Australians. The age profile of mortality indicates that significant progress towards closing the gap can only arise via sustained reduction in excessive rates of Indigenous adult mortality, especially among those over 40 years old. This is further demonstrated by establishing the year in which infant mortality rates (IMRs) and expectation of life at birth were the same for the total population as they are now for the Indigenous population. Current Indigenous IMRs are at a level last seen for all Australians back in the early 1950s. For overall life expectancy, the corresponding reference point is the early 1920s. Given these excessive time lags in the profile of mortality, even if the pace of mortality change that has occurred among the total Australian population were to now apply to the Indigenous population, it would still take another 40 years before the Indigenous IMR reached the current level observed for the total population. Moreover, unless program efforts aimed at improving health outcomes for Indigenous Australians are dramatically enhanced, with commensurate effects, it will take another seven decades before the expectation of life at birth among Indigenous Australians reaches the level currently recorded for the total population. Clearly, the timetable for Indigenous mortality improvement is long-term, and this adds further weight to the opportunity cost argument that there is an imbalance between health expenditure on Indigenous Australians and their needs