Pew Research Center surveyed 2849 internet users. Two out of five people reported having been victims of some form of online harassment. 27% of internet users have been called offensive names; 22% have had someone try to purposefully embarrass them. One out of four had seen someone being physically threatened online. 45% of harassment victims thats 18% of all internet users have been plagued by the more severe forms of harassment. Those more severe forms of abuse tend to be directed disproportionately at women particularly young women.”]
Source: https://nakedsecurity.sophos.com/2014/10/24/how-to-kill-a-troll/