gilded, that figure isnt correct. 68.3% were religious in the 2011 census (one of the lowest in the world). The no-religion percentage has alomst doubled since the 1980's as well.
Take a look at youth rates of no religious belief... As religion is taken out of school and children and better educated, the rates of relious belief are declining.
Wont be long now until majority of Australians are not religious.
