18, swear A LOT... but that's cause I'm half Danish and for some reason swearing in foreign languages while speaking Danish is completely normal. Even some of my teachers do it. However my swearing becomes much more elaborate when I am actually pissed off(there, I did it again), so I guess swearing often doesn't make it any less effective.
In a day with my friends I might swear 300 times but I very rarely swear casually or in anger online, especially on nice forums like this. In fact I don't get angry online, unless I am already in a very bad mood.
Recap: 18, swear about 300 times a day but it means very little unless I am angry.