Census 2016 puts on display the increasing diversity in Australians' relationships

The types of romantic relationships Australians have, as well as the way they are recognised and measured, have changed dramatically in the last 30 years.

Much of the change in partnering has been in response to changing legal and social norms. Childbearing has been decoupled from intimate relationships by the widespread availability and use of contraception and the availability of abortion. Divorce is easier to access; women play a much greater role outside the home.

These and other forces have led to delays in marriage, increasing co-habitation (couples living together), and a larger proportion of the population who re-partner or have more than one relationship throughout their adult life.

Key trends

Results from the 2016 Census, released today, allow us to track marriage and co-habitation trends for both heterosexual and same-sex couples.

In 2001 and 2016, around 40% of Australians were classified as single. By age, this pattern declines until the mid-30s, and then increases in older ages due to divorce and widowhood.

The pattern is more obvious for women – particularly in the older ages, as they are more likely to experience the death of their partner.

There has been a slight increase in co-habitation overall to 10% of Australians, and a corresponding decrease in marriage to just under 50%.

What has changed the most in these relationship patterns is that co-habitation was predominantly confined in 2001 to people in their 20s and 30s. In 2016, cohabitation is also a significant feature for people up to their mid-60s.

Same-sex couples have been identified in the census since 1996. Over each successive census, the number of couples identifying as same-sex has increased. In 2016, 46,800 couples were same-sex – an increase of 39% from 2011.

The 2011 Census showed people in same-sex couples are, on average, younger, more educated, employed in higher-status occupations, and have higher incomes.

The 2011 Census allowed same-sex couples to identify their relationship as a marriage for the first time. As would be expected, the numbers are small (1,338) – but they will rise over time, as more people travel overseas to marry legally and in the event Australia legislates for marriage equality.

What all this means

The rise of co-habitation has led to speculation that marriage is out of fashion and could disappear altogether. Our research shows the institution of marriage is not outdated. The nature of marriage is evolving, as people manage the changing role of intimate relationships in their lives.

It is also true that the marriage equality debate will lead to a re-imagining of marriage for both homosexual and heterosexual couples. Most Australians still marry, and there is no evidence that marriage will disappear – despite predictions.

However, while marriage may have lost its practical importance, its symbolic importance still seems to be high. In many ways, getting married is still seen as a marker of achievement.

Perhaps new ways of forming relationships and childbearing are not a threat to marriage: they may be a signal of the fact that more options are now available.

The distinction between same-sex and heterosexual relationships is complicated by the measurement of gender itself.

For the first time, the 2016 Census allowed non-binary gender as a response to the question of sex, although people identifying as other than male or female were required to use the paper form or to request a special online form. This would have significantly affected the overall count of people who identify as neither male nor female.

There were 1,300 validated responses that indicated a sex other than male or female. The Australian Bureau of Statistics has also estimated an additional 2,400 people responded both male and female on the paper form.

Overall, the census shows a decrease in the proportion of Australians who are married, and an increase in co-habitation of both heterosexual and same-sex relationships. We predict this will continue to rise in future censuses.