Measures of the potential economic implications of a given age structure can be combined with data on labour force status to produce a range of dependency ratios. These are shown in Table 3.3 for the Aboriginal population of the Northern East Kimberley in 2001, with comparison drawn from Western Australia as a whole. The childhood dependency ratio is the simplest of these measures and expresses the number of children in the population (aged 0-14 years) as a ratio of the working-age population (defined here as aged 15-55, given the significance of adult morbidity). Obviously, a ratio of 1.0 would indicate that the size of the two age groups is the same and that there is one person of working age for every child. A figure greater than 1.0 indicates more than one child to each person of working age, and less than 1.0 indicates less than one child to each person of working age. Obviously, this only provides an indication of the ratio of potential economic providers to dependents, as it takes no account of the economically inactive.

In the study region, the childhood dependency ratio was 0.73 which is similar to the 0.72 reported for Aboriginal people generally in Western Australia. In effect, there are 0.7 Aboriginal children to each Aboriginal adult of working age. While this may appear to be a favourable ratio at one level, it represents far more children per adult compared to the ratio of 0.29 recorded for the non-Aboriginal population of the region.

More refined measures of dependency incorporate some indication of the ability of working-age adults to support others. The childhood burden, for example, is defined as the ratio of the number of children to the number of employed persons. Once again, a figure of 1.0 indicates parity. According to census-based estimates, there were 1.3 Aboriginal children to each employed adult if all those engaged by the CDEP scheme are considered to be in employment. If, however, this calculation is based on those employed only in non-CDEP work, then the ratio is much higher at 3.9. The fact that the equivalent ratio for all Aboriginal people in Western Australia is much lower at 2.3 underlines the considerable reliance on CDEP in the study region as the primary support mechanism for large numbers of child dependents.

Another measure is provided by the dependency ratio which represents the ratio of children and economically inactive adults to the labour force (those employed plus those unemployed). This produces an average of 2.7 dependents per economically active person, but if the focus were solely on those in mainstream employment the dependency ratio would be much higher.

Finally, the economic burden is a ratio of the number of children and economically inactive persons (including here those unemployed) to employed persons. This shows that for each employed Aboriginal person (including those in the CDEP scheme) there are 2.6 other Aboriginal people who are not employed, a figure similar to the state average. If, however, those in CDEP are excluded from the economically active then the economic burden in the study region is almost double the state average at 9.1 dependents per income earner.

From a regional planning perspective, then, the youthful Aboriginal age profile is a key demographic feature when set against the relatively poor labour force status of adults. In effect, there are 9 dependents, on average, for each Aboriginal employee in the mainstream labour market. This represents a notably higher economic burden for the regional Aboriginal population than recorded for the Aboriginal population generally in Western Australia. However, perhaps of more significance in the local context of access to resources and consumer spending, is the fact that the burden is massively higher than observed among non-Aboriginal residents of the region (0.5 dependents per income earner) with whom Aboriginal residents can draw direct comparison.