Account for the significant changes in Australia's religious landscape since 1981.
Australia's religious landscape has had significant changes since 19811 to 2011. When looking at Christianity as a whole, adherents have decreased. This is reflected in the decline from 77.1% in 1981 to 61.1% in 2011.
You could be a little more succinct here - "The number of Christian adherents decreased from 77.1% in 1981 to 61.1% in 2011," would be all you need instead of those two sentences. The 1986 census was the first time Catholics were the highest Christian denomination, leading with 26.1%. Catholicism and Anglicanism are revealed to be the most dominant Christian denominations with Catholics being 25.3% and Anglicans being 17.1% in 2011.
This is not a change - Focus on the things that are different, make comparisons. Up until the 1981 census, Uniting Church consisted of no adherents.
This is because the Church was only formed in 1977 as an ecumenical movement by the Congregational, Methodist and Presbyterian churches. Adherents, within the Uniting Church, have now increased to the total of 5% in 2011. There has been a continuous increase in 'Religious Traditions other than Christianity'
due to changing immigration laws.
Be more specific about this last bit. This is evident through the change from 1.4% of other Religious Traditions in 1981, to approximately 7% in 2011. 'People with no religion' have increased since being 10.4% in 1981, to 22.3% in 2011.
This could be due to the idea that people are more interested in factuality and then lean towards New Age Religions such as Scientology. Try to make your arguments strong, don't say "could be", because the marker sees that and thinks you aren't really sure what you are talking about.