Surveys shown that Burlington High School is unsafe; proof that security cameras aren't helping

According to the 2011 and 2012 Burlington Index Report, the Burlington High School's safe school index is at a low.  You can find the reports here.  http://www.burlington.k12.ia.us/index.php?option=com_docman&task=cat_view&gid=42&Itemid=58

2011

2012

Despite having cameras all around the school and the doors of classrooms and entrances are locked down since 2006, the safety index is still at a low rate.  

Its questionable whether there is any enforceable actions done to reduce the violence.  Its also questionable about whether these statistics are accurate or not.  For example, the 2012 version of the states that student's physical and emotional safety are high.  

Another thing to consider is that there is a statement within the documents that says that these are surveys.  In 2012, only 71% of students filled out a survey while in 2011 data shows no statistic of how many had participated.  The problem with surveys is that not all the students are always accurate and truthful.  Some rush the survey while some others lie in some of the answers.  

What makes this interesting of a statistic is the fact that despite the surveys being inaccurate in the most part, the safety index of the school is still low.  

I'm curious about the documents from before 2010.  Unfortunately, the BCSD's website has no statistics showing the safety from previous years.