Catholic Church in Ireland
In the 2016 Irish census 78.3% of the population identified as Catholic in Ireland; numbering approximately 3.7 million people. Unlike Catholics in the United States, Ireland has seen a significant decline from the 84.2% who identified as Catholic in the 2011 census.
Irish Australians
According to census data released by the Australian Bureau of Statistics in 2004, Irish Australians are, by religion, 46.2% Roman Catholic, 15.3% Anglican, 13.5% other Christian denomination, 3.6% other religions, and 21.5% "No Religion".