PTSD prevalence

Approximately 5.2 million American adults ages 18 to 54, or about 3.6 percent of people in this age group in a given year, have PTSD.
About 30 percent of Vietnam veterans experienced PTSD at some point after the war. The disorder also frequently occurs after violent personal assaults such as rape, mugging, or domestic violence; terrorism; natural or human-caused disasters; and accidents.
Studies have found from 1 to 14 percent of people suffer from post-traumatic stress disorder at some point during their lives. The findings vary widely due to differences in the populations studied and the research methods used.

Among people who have survived traumatic events, the prevalence appears to be much higher. The disorder may be particularly prevalent among people who have served in combat. For example, one study of veterans of the Vietnam War (1959-1975) found that veterans exposed to a high level of combat were nine times more likely to have post-traumatic stress disorder than military personnel who did not serve in the war zone of Southeast Asia.