A limitation of this research is the study population does not include ex-serving members who separated prior to 1 January 1985. The starting point for this study population is the ex-serving members with at least one day of service since 1 January 1985. At the end of 1985, almost 6,100 members had separated. By the end of 2019, this had grown to comprise nearly 261,000 living members. Due to the method used to assemble the study population, as members leave permanent and reserve service, they are counted as members of the ex-serving study population until they die.
The number of members separating from permanent and reserve service remains relatively stable at an average of around 7,400 each year. There was a larger number of separations of around 14,300 in 2016 driven by an increase of separations by reserve members. This increase could potentially be due to the transition to the Total Workforce Model (now known as Total Workforce System) at this time (Department of Defence, 2017).
Figure 4: Ex-serving members as of 31 December, 1985–2019
Source: AIHW analysis of linked Defence Historical Personnel data–PMKeyS–NDI data 1985–2019.
Department of Defence 2017. Defence annual report 2016-17. Canberra: Department of Defence.