Apparently, your friendship circle starts to shrink at a certain age. The bad news: It's a lot sooner than you might have expected.

According to a study from the Finland's Aalto University School of Science and Oxford University’s Department of Experimental Psychology, both men and women start to lose friends when they hit 25.Researchers analyzed calls made from mobile phones within certain time periods, which ranged from a month to a full year. The anonymized call records were finally narrowed down to 3.2 million users — for whom both age and gender were available.If you're asking why researchers used call data over texts, take into account the fact that this research was done in 2007.The end result: Men and women called different people on a regular basis most often at the age of 25.Apparently, things just get worse for men. At age 39, most men were calling only about 12 people regularly. Women were calling closer to 15.The data also showed that from ages 45 to 55, friendship peaks level out; but once again, women still had more contacts than men.