Plus: the reason why.
Movies and television shows love to give mixed messages about who exactly is happier: the married camp or the single camp. Married couples (who aren't newlyweds) are often portrayed as boring, sexless, unhappy fuddy-duddys while Single women are usually shown to be lonely, overlooked, and unhappy until they find someone. (We're majorly generalizing, of course.)
So who's really happier?
Researchers John F. Helliwell and Shawn Grover found that married people are happier than people who are going solo.
The findings come from a Gallup World Poll and other studies. Another interesting finding is that couples who are in their 40s and 50s especially feel the positive effects of marriage, because it often counteracts a mid-life crisis.
Of course the quality of your marriage factors in, too. The study found the key to married couples' happiness is that many claimed their marital partner is also their best friend, which makes sense, especially since research suggests sex ebbs and flows over the course of a long marriage, so having something to talk about is a nice back-up.