The population of Mutitjulu has grown substantially and at a rate above the regional average since the community was established in 1985. There have been several counts of the population since then, and five of these are presented in sequence to chart the growth in numbers. Overall, they indicate an increase in the usually resident population from 140 in 1986 to 385 in 2000. This represents an annual rate of growth of 12.5 per cent, which is far above the rate of 3.1 per cent per annum recorded for the wider central Australian region.

Mathematical projection

The first set of projections involves a simple continuation of population trends observed since 1985. They are generated to provide an initial sense of the possible range of future population sizes. A further reason is that, anecdotally, one scenario proposed for Mutitjulu is exponential growth. Mathematical projections provide a measure of what this would entail numerically. These estimates are very crude as they fail to account for the effects of changing age structure on population growth and the manner in which this influences other demographic processes such as fertility and mortality.

Projection based on share of regional growth The second (main) projection attempts to measure how birth rates, death rates, migration, and age structure might affect the future population size of Mutitjulu. This is done by projecting the population of the wider region to which Mutitjulu is socially, culturally and economically linked, and then by allocating a share of this future regional population to Mutitjulu. The region selected for this purpose approximates that serviced by the Ngaanyatjarra-Pitjantjatjara-Yankunytjatjara (NPY) Women's Council.

Estimating the future population of Mutitjulu using this method thus involves a two-stage process:

• the population of the NPY region is projected in five-year stages to 2021 using a cohort component method;
• then, the future population of Mutitjulu is derived as a percentage share of the regional population. This procedure is based on the assumption that the historic trend in Mutitjulu's share of the regional population will continue.

Two sets of projections are developed for the NPY region-a high series and a low series. The former assumes that fertility levels will remain constant, the latter that fertility will decline. No change is envisaged in the level of mortality, while migration into the region is assumed to be counterbalanced by migration out of the region.

Projection results

Mathematical

The mathematical projections produce two estimates of population size in 2021:

• a population of 763, if the average annual increment observed since 1985 continues (arithmetic growth);
• a population of 1,755, if the numbers added to the population each year increase in compound fashion (geometric or exponential growth)

However, because exponential growth is rarely achieved, it would be unusual indeed if the future population of Mutitjulu approached the higher estimate. It is presented simply to identify an absolute upper limit of probability.

Mutitjulu share of regional growth

The cohort component projections for the NPY region indicate, for the high series, a population rising from 4,909 in 1996 to 6,942 in 2021; for the low series, they indicate a population rising from 4,909 in 1996 to 6,601 by 2021.

The Mutitjulu population is then calculated as a percentage share of these regional estimates. In 2000, the population at Mutitjulu represented 7.4 per cent of the NPY region, by 2021 it is estimated to represent 12.9 per cent. This produces a high series population of 893 by 2021 and a low series figure of 849. The variation in projected populations is deliberately calculated to be limited because of the high degree of uncertainty surrounding much of the demographic data.

Factors supporting a growing share of regional population at Mutitjulu

These factors include:

• the continued emergence of the community as a regional centre;
• ongoing expansion of tourism;
• the related prospect of further economic development and associated employment and income-generating opportunities for Anangu (Aboriginal people); and
• continuing infrastructural developments, especially housing.

Factors that may limit continued expansion

These factors are less obvious but stem largely from the overwhelming evidence about the growth experience of other settlements across central Australia. There appears to be a ceiling on the size of Aboriginal communities in central Australia at around the 500 population level. This may result from the tendency for smaller, more politically cohesive residential groupings to break away from overcrowded centralised settlements with their attendant social pathologies, and set up smaller outlying settlements, or outstations.

Interpretation

Over the next 20 years it is possible to envisage a number of factors that are likely to encourage further population growth, but it is equally the case that the effect of these might be dampened by other factors which limit continued expansion. When these factors are considered, the population range of between 850 and 890 projected for Mutitjulu by 2021 appears likely to represent a ceiling on future numbers rather than being a step within an ever-rising level. Certainly, it is difficult to envisage Mutitjulu (or any other Aboriginal community in the region) growing to a point where it represents much beyond 13 per cent of the regional population.

ISBN: 0 7315 2646 5

ISSN:1036 1774