Nearly eight out of 10 Australians responded to the survey, or 12,727,920 people out of the 16,006,180 who were posted one — a participation rate of 79.5 per cent.All age groups had higher than 70 per cent participation, with older voters having a slightly higher turnout.Those aged 70 to 74 were the most likely to respond to the survey, with 89.6 per cent of eligible Australians in this age group voting. The participation rate was lowest among those aged 25 to 29 at 71.9 per cent.But the youngest group of eligible Australians (aged 18-19 years) were more likely (78.2 per cent) to participate than any other age group under the age of 45. ABC