A new study has shown just how rapidly the attitudes towards adults in same-sex relationships can change. A recent survey has found that the proportion of people living in the US who are accepting of gay relationships has nearly quadrupled in just under 25 years, increasing from only 13 percent in 1990 to 49 percent in 2014. Not only that, but the number or adults who admit to having a same-sex sexual experience has doubled over the same period.

While the acceptance of same-sex sexuality has increased in all generations, there was an even greater and more dramatic shift among the under 30s, which has risen from 15 percent in 1990 to an impressive 63 percent in 2014. This reflects the general trend for the younger generations to be more accepting of homosexual and lesbian activity and their overwhelming support of same-sex marriage, where it is reported that three out of four millennials in the US were in favor of legalizing it.

The report has also looked into those who admit to having had same-sex partners. Here, they found that the number of adults reporting this had doubled from 4.5 percent to 8.2 percent in men, and from 3.6 percent to 8.7 percent for women. The biggest shifts in those reporting same-sex sexual experiences occurred among white people living in the South and Midwest of the country, with little change in the reported rate seen among black people, which the authors suspect is probably related to the fact that homosexuality is still highly stigmatized in these communities.

The dramatic changes in attitude recorded are not necessarily solely down to a generational effect but, the authors say, is more likely to be related to time. This suggests that there is a cultural influence on the changing perspectives. They point to a shift away from strong rules meted out in society as seen in the past, and movement towards individualism, where people can engage in whatever behaviors they like.

“These large shifts in both attitudes and behavior occurred over just 25 years, suggesting rapid cultural change,” explains Jean Twenge, a professor of psychology at San Diego University, and co-author of the study published in Archives of Sexual Behavior. “These trends are another piece of evidence that American culture has become more individualistic and more focused on the self and on equality," she said. "Without the strict social rules common in the past, Americans now feel more free to have sexual experiences they desire.”

The study used the data collected from 30,000 Americans who partake in the General Social Survey, a nationally reprehensive survey that has taken place since 1973. It has always asked about attitudes towards same-sex relationships, but from the late 1980s, however, they began collecting data about sexual partners. In the years leading up to 1990, the adults who believed that sex between two adults of the same gender was not wrong hardly changed at all (from 11 percent to 13), making the shift since even more profound.