Standardised mortality in Australia
The numbers of deaths increase, whilst mortality rates decline.
Why were the numbers of deaths in Australia higher in 2021 than in the previous year?
Three factors influence death counts in a population:
- Population size: a larger group is more likely to experience people dying.
- Age structure: mortality risks increase with age, so older populations have more deaths.
- Mortality rates within age groups: in age bands, these rates change in time and space.
Differences in these factors result in changes to the numbers of deaths.
Australia has a growing population, which is also getting older. At the start of the century, there were around 19m Australian residents, with a median age of 35. By September 2020, the residential population was about 25.7m people. The median age was also above 37 years.
Even with mortality rates declining, a growing and ageing population is overwhelming. That leads to increased numbers of deaths each year. Improvements in mortality rates are an insufficient counterbalance.
What if we look at age-standardised mortality? This is a statistical procedure. First, collect death statistics by different age groups. Second…
