According to the Rape Abuse and Incest Network:

• One out of every six American women have been the victims of an attempted or completed rape in their lifetime (14.8 percent completed rape; 2.8 percent attempted rape).
• 17.7 million American women have been victims of attempted or completed rape.
•  Nine  of every 10 rape victims in 2003 were female.
• About 3 percent of American men — or 1 in 33 — have experienced an attempted or completed rape in their lifetime.
• Ages12-34 are the highest risk years.
• Girls ages 16-19 are four times more likely than the general population to be victims of rape, attempted rape or sexual assault.
• College-aged women are four times more likely to be sexually assaulted
• In 2006, there were 272,350 victims of rape, attempted rape or sexual assault. (These figures do not include victims 12-years-old or younger.)
• Sixty percent of rapes/sexual assaults are not reported to the police. Those rapists, of course, never spend a day in prison according to a statistical average of the past five years. Factoring in unreported rapes, only about 6 percent of rapists ever serve a day in jail.
• Almost two-thirds of rapes were committed by someone known to the victim.
    • Seventy-three percent of sexual assaults were perpetrated by a non-stranger.
    • Thirty-eight percent of rapists are a friend or acquaintance.
    • Twenty-eight percent are an intimate.
    • Seven percent are a relative.
• Victims of sexual assault are: three times more likely to suffer from depression; six times more likely to suffer from post-traumatic stress disorder; 13 times more likely to abuse alcohol; 26 times more likely to abuse drugs; four times more likely to contemplate suicide.

http://www.rainn.org/statistics