John Grohol investigates:
Virtually all people swear, and people swear pretty consistently throughout their lifetime from the moment they can speak to the day they die. Swearing is almost a universal constant in most people’s lives. Research, according to [Timothy Jay], has shown we swear on average from 0.3% to 0.7% of the time a tiny but significant percentage of our overall speech (frequently-used personal pronouns occur at approximately 1.0% rate in speech). Swearing is more common than you might think. But personality research suggests that people who swear more, not surprisingly, score higher on traits such as extraversion, dominance, hostility and Type A personalities. Swearing is not just for the uneducated or people of a lower socioeconomic class it knows no social boundaries in its expression.