Sex

What percentage of the population is gay? (Trust us, the number is higher than you think...)

With the same-sex marriage postal-vote slips being sent out to households across the country this week, do you actually know how many Australians your vote will affect?

So, how many gays and lesbians are there in Australia? A straight question deserves a straight answer, right? Well, when it comes to human sexuality the answers might not be as straight we some of us think.

According to a new study by Roy Morgan Research, the proportion of Australians who identify themselves as gay or lesbian is increasing.

In fact, those who say they are homosexual has been on the up since 2008 when 2.4 per cent of the population agreed with the statement: 'I consider myself a homosexual.' By 2011 that figure was 3.1 per cent. And by 2014 the figure had risen to 3.4 per cent.

But these figures don't tell the whole story. These latest figures show that 4.6% of Australian teenagers (14-19) now agree they are homosexual (up from 2.9% in 2006-08), rising to a peak of around 1 in 15 people in their 20s (6.5%, up from 4.4% in 2006-08).

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But this figure drops to 4.2 per cent for people in their 30s, 2.8 per cent in their 40s and drops further still to 1.7 per cent among those aged 50 and above, although all these figures represented increases from the previous survey in 2011.

The fact that there is a drop consistent across the age groups raises some challenging questions such as, does homosexuality suddenly begin to disappear when you reach 30? Clearly, the answer is no. So what is really going on here?

The most like answer, says Roy Morgan Research CEO Michele Levine, is that the survey respondents truthfulness dissolves, rather than their homosexuality.

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"One can intuitively understand why the rate rises from 14-19 to 20s, as more young people 'come out'," says Michele. "But the subsequently decreasing prevalence suggests some older respondents are less candid.

"Whether this is due to their being 'in the closet', more concerned with privacy, or perhaps less agreeable to the black-and-white nature of the question, we might take the 20s rate - 6.5% today, but potentially still not done rising - as the most accurate and forthright overall figure.

"Across all age groups, men are more likely than women to agree that they consider themselves as homosexual."

She says that the rising rate across all age groups shows that people who consider themselves homosexual are more open today than ever before. "Finding out the 'real' number, therefore, is less about getting a head-count and more a gauge of just how open we are," she says.

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