Americans in their 50s and 60s are having more extramarital sex than anyone else

• In 2016, 20% of older Americans said they'd had sex with someone other than their spouse; 14% of younger Americans said the same.

• This is a stark contrast to the early 1990s, when older Americans were less likely to have extramarital sex.

• Americans in their 50s and 60s report the highest rates of extramarital sex, which might have to do with the fact that they became adults during the sexual revolution.

Every year since 1991, the General Social Survey has asked Americans a potentially uncomfortable question: "Have you ever had sex with someone other than your husband or wife while you were married?"

And every year, about 16% of respondents answer "yes."

Yet that stable 16% figure masks some important - and surprising - changes around who exactly is having extramarital sex.

A recent analysis by Nicholas Wolfinger, a professor at the University of Utah, published on the conservative-leaning Institute for Family Studies blog, suggests that older Americans (55 and older) are now more likely to have sex outside their marriages than younger Americans (55 and younger).

In 2016, 20% of older respondents said they'd had sex with someone other than their spouse; 14% of younger respondents said the same.

That's in sharp contrast to the early 1990s, when older Americans were less likely to have sex outside their marriages than their younger counterparts.

Things get tricky when you start trying to explain this phenomenon. It can't be simply that older people are having more extramarital sex simply because they've been married for longer - because up until 2004, older Americans were straying less.

Wolfinger notes that people born between 1940 and 1959 report the highest rates of extramarital sex - and these are the people who became adults during the sexual revolution. As Wolfinger writes: "Perhaps some people do become more likely to have outside sex partners as they age, but only if they grew up during the sexual revolution of the 1960s and 1970s."

The introduction of medications such as Viagra may also help explain why older Americans recently started having more extramarital sex, Wolfinger says.

It's important to keep in mind that the GSS doesn't ask people whether they were "cheating" - some people may be in open marriages or may have made other arrangements with their partner that allow them to have sex with other people.

The GSS also asks about having sex with someone other than your spouse, meaning people in unmarried relationships who have sex with someone other than their partner aren't included. Nor are people who have "emotional affairs" with someone other than their partner.

But if you are in a marriage affected by infidelity, there are steps you can take to repair the relationship. As M. Gary Neuman, who developed the "Creating Your Best Marriage" video program, told Business Insider, the cheater has to feel some remorse and want to change their life and the victim has to make sure the cheater has completely stopped cheating.

Remember, too: We tend to underestimate the likelihood that our partner will cheat on us.

In one University of Calgary and McMaster Children's Hospital study, university students in heterosexual dating relationships said the average person of the opposite sex has about a 42% chance of cheating on their partner. But when it came to their own partners, participants estimated that there was about a 5% chance that their partner had already cheated on them and about an 8% chance that they would cheat on them in the future.

Meanwhile, about 9% of participants said they'd really strayed.