In an analysis of the latest census figures, Mr Dixon said that as the total population grew at a faster rate, 5.8 per cent, than the Catholic population, the proportion of Catholics in the Australian population has declined slightly, from 26.6 per cent to 25.8 per cent.
The 2006 Catholic Census population was 5.13 million, up from 5 million in 2001 - an increase of 125,260, or 2.5 per cent.
There were substantial falls between 2001 and 2006 in the number of people identifying themselves as belonging to the Anglican, Presbyterian and Reformed, Salvation Army, Churches of Christ and Uniting Church traditions, Mr Dixon noted.
On the other hand, there were large increases in the number of Buddhists, Hindus and Muslims. The Brethren, the Mormons and the Pentecostals also recorded strong growth, he said.
NSW recorded both the highest number and the highest proportion (28.2 per cent) of Catholics in 2006. The ACT, which had the highest proportion of Catholics in 2001 (29.1 per cent), slipped into second place in 2006, with (28.0 per cent).
The strongest growth in the number of Catholics, however, was in Victoria and Queensland, where the Catholic population increased by about 46,000 in each State. By contrast, the Catholic population of the Northern Territory fell by over 4,000, in line with the fall in the overall population there. The State with the lowest proportion of Catholics was Tasmania, with 18.4 per cent.
The Northern Territory had by far the youngest Catholic age profile, with 25 per cent being aged under 15 years, and only 5.3 per cent aged 65 years or over. In South Australia, by contrast, only 19 per cent were aged under 15, while 15.7 per cent were aged 65 or over.
Mr Dixon said that it should be noted that totals can vary slightly from table to table due to ABS techniques designed to protect confidentiality.
Meanwhile, News.com.au noted that the Census showed that nearly one in five Australians are without religion, while more couples are choosing not to have children and single-parent families are also on the rise.
However, Christianity is still the dominant religion, with 12.7 million followers nationwide. But as a proportion of the population, Christianity dipped from 71 per cent to 64 per cent.
The Sydney Morning Herald noted that except for Brisbane, Sydney is the most Christian city in Australia, and Pentecostalism grew fastest in NSW, by 48 per cent, over the past decade. Census figures show Pentecostalism, whose churches include the 19,000-member strong Hillsong Church and Christian City Church, has cemented its place as the nation's fastest-growing Christian religion.
The paper says that Sydney is the epicentre of tectonic shifts in the Australian social landscape, with an increasingly diverse ethnic and religious mix, an ageing population, a continuing decline in the traditional family unit and big changes in the way we live and house ourselves.
Catholics and the 2006 Census - a brief look (ACBC Media Release, 27/6/07)
Census figures show more Australians have no religion (News.com.au, 27/6/07)
Pentecostal revolution in the suburbs (Sydney Morning Herald, 28/6/07)
Good or bad, Sydney is the mover and shaker (Sydney Morning Herald, 28/6/07)
Meet your average Aussie (The Age, 28/6/07)
LINKS (not necessarily endorsed by Church Resources)
Australian Bureau of Statistics
Pastoral Projects Office
Catholics told to stand up and be counted for census (CathNews, 4/8/06)
Pell blames Sunday sport for decline in mass attendance (CathNews, 17/12/03)
Australia's Catholic population tops 5 million (CathNews, 18/6/02)