According to data from a national survey of nearly 30,000 people has found Americans are having less sex than they used.

A new study analyzing 26,000 people has found married couples and millennials are less sexually active than previous generations. In fact, researchers report that people are having sex on average nine times fewer a year in 2010 to 2014 compared with 1995 to 1999.

The study was published in the Archives of Sexual Behaviour, and researchers suggest that part of the decline in sex is due to the fact fewer young people are in a relationship. As a result, they are having sex on average less often than people in relationships, according to Jean Twenge of San Diego State University.

“These data show a major reversal from previous decades in terms of marriage and sex,” said Twenge. “In the 1990s, married people had sex more times per year than never-married people, but by the mid-2000s that reversed, with the never-married having more sex.”

Twenge previous research has shown that millennials are also having sex far less often than before. Researchers say that millennials are likely to have had eight sexual partners by the time they turn 45. Meanwhile, Baby Boomers had an average of 11 partners by the time they were 45.

“Despite their reputation for hooking up, Millennials and the generation after them – known as iGen or Generation Z – are actually having sex less often than their parents and grandparents did when they were young,” said Twenge. “That’s partially because fewer iGen’ers and Millennials have steady partners.”

That said, millennials are still having sex more often than anyone else. Americans in their 20s had sex about 80 times a year, in comparison to people in their 60s who are having sex about 20 times a year.

This news comes after research has shown having sex improves job satisfaction and work engagement. Research has shown that a healthy sex life improves job performance and satisfaction.

Having a healthy sex life boosts employees’ job satisfaction and engagement in the office, according to an Oregon State University research study.

A study examining work and sex habits of married employees found that those who prioritized having sex gave themselves an advantage over those who did not. Research suggests that they were more likely to be become involved in their work assignments and enjoy their job, according to Keith Leavitt, associate professor in OSU’s College of Business.

“We make jokes about people having a ‘spring in their step,’ but it turns out this is actually a real thing and we should pay attention to it,” said Leavitt, an expert in organizational behavior and management. “Maintaining a healthy relationship that includes a healthy sex life will help employees stay happy and engaged in their work, which benefits the employees and the organizations they work for.”

The research findings were published in the Journal of Management and researchers also found that bringing work-related stress from home negatively affected their sex lives. In a time where employees are an arm’s reach from emails and work assignments, thanks in part to their smartphones, Leavitt says, employees are sacrificing their personal life for work.

Biologically, research has shown that sex releases the hormone dopamine, a neurotransmitter associated with the reward centers in the brain. In addition, oxytocin is also released, which is associated with bonding and social attachment. Leavitt argues that sex provides emotional and mental benefits that extend beyond after sex.

Researchers examined 159 married employees over the course of two weeks and asked them to complete two surveys each day. Scientists found that over the course of two weeks, employees who had sex more often had reported more positive moods the following day, and elevated mood levels in the morning after, which led to higher work engagement and job satisfaction.

“This is a reminder that sex has social, emotional and physiological benefits, and it’s important to make it a priority,” Leavitt said. “Just make time for it.”

This news comes after Pornhub, the pornographic video streaming website, announced a new initiative to provide free sex education for those interested in learning about sexually transmitted diseases, intercourse, sexuality and other common topics related to sex.