Here's how much sex the happiest couples are having according to science

When you're in your mid-late teens, it is easy to believe that sex is the key to happiness. Due to the raging hormones in your body, you are constantly randy and looking to hump anything that moves. However, as you grow up and begin to slow down, so does your sex drive. Despite this, sex is still a vital cog in a smooth relationship and is vital when it comes to maintaining a balanced, pleasant and happy relationship.

But, while you may think that the happiest couples are those who are getting freaky on the regular, you would be mistaken... kind of. It turns out then when it comes to sex, less is actually more - and we have the science to prove it.

According to a recent survey that was published in the scientific journal Social Psychology and Personality Science, the happiest couples don't get jiggy with it every single day, they actually go at it like a pair of rabbits around once a week. Also, according to the same survey, those who were having sex less than once a week were left less fulfilled.

However, in a separate study conducted by the Kinsey Institute revealed that the average amount of sex that couples have is purely based on age. According to the research, couples between the ages of 18 - 29 have sex 112 times a year, averaging out at twice a week.

But, once you hit the age of 30, that number falls to 86 times a year. Then, when you hit the dreading 40, it falls even further, to 69 (lol) times a year. Of course, this is all completely understandable as the older you get, the more responsibilities you have. On top of this, as your body gets older, it begins to decline - with the likes of arthritis and fatigue likely to take their toll on the amount of sex you have.

“Some people want to have sex every day, and they are. Other people have other priorities, so sex isn’t on the top of their list, so they are having it less,” marriage therapist and professor at the University of Southern California, Mary Andres, told USA Today.

According to Dr. Sanam Hafeez, the main reason couples struggle in the love-making department is because of things like stress, medical issues, smartphones and declining connections. But, Hafeez does say that doesn't mean your sex life is over, just that you need to put a bit more effort in.

“Check in throughout the day. A kissy face emoji or a quick message sending love keeps the connection going,” Hafeez explained to NBC News. “Also, something as simple as walking together after dinner without phones, or dancing, can get good brain chemicals flowing".

Of course, it should be noted that there is no such thing as the perfect amount of sex. All relationships are based on communication, so it's all about finding a happy medium between too much and too little. In other words, don't worry about comparing your sex life to other people's, it's pointless.