I recently put a digest of Australian violent crime statistics up on my website. http://www.aikidorepublic.com/self-defence
(the page is still under development but its a start) Its really sobering stuff. If sexual assault is closely examined you find out that it happens mostly in someones house and by someone you know (and very often a relative)...it really turn things like self defence training on its head.
On the subject of guns and without wanting to start a flame war and continuing to head further off topic in the recent past Australia made moves to make it more difficult to own guns and keep them in the house.
I think the rationale was based on the statistics of incidents between those known to each other (80% of homicides, 60% sexual ) and in a home or dwelling(57% homicides, 67% sexual) and removed the opportunity to grab in the heat of the moment. It has lead to a significant decrease in the homicide rate.
Over whelmingly violent crime statistics point to common risk factors like young males (both the perp and victim), drugs and alcohol.
Heading really off topic It might seem that awareness / ma-ai training might be the most important skill in terms of self defence and seems to be a common thread of the collective wisdom in this thread