Year | Number of Attacks1 | Percent | Mean | Variance | Standard Deviation | Coefficient of Variation |
2007 | 0 | 0.00% | 2.4 | 5.76 | 2.40 | 1.00 |
2008 | 0 | 0.00% | 5.76 | 2.40 | 1.00 | |
2009 | 1 | 4.17% | 1.96 | 1.40 | 0.58 | |
2010 | 0 | 0.00% | 5.76 | 2.40 | 1.00 | |
2011 | 20 | 83.33% | 309.76 | 17.60 | 7.33 | |
2012 | 2 | 8.33% | 0.16 | 0.40 | 0.17 | |
2013 | 0 | 0.00% | 5.76 | 2.40 | 1.00 | |
2014 | 0 | 0.00% | 5.76 | 2.40 | 1.00 | |
2015 | 0 | 0.00% | 5.76 | 2.40 | 1.00 | |
2016 | 1 | 4.17% | 1.96 | 1.40 | 0.58 | |
Sum | 24 |
| Average | 34.84 | 5.90 | 2.46 |