Should wearing ski helmets be mandatory

As I started to research my project I found a lot of good and helpful webpages.  Like how a lady named Natasha Richardson died in March 2009 for not wearing a ski helmet.  I also found out in 2008 more than half of skiing deaths a year are from not wearing a ski helmet.  I found this on U.S. Consumer Safety  Commission.  I have not had any trouble so far on my project and it is going fine.