| Value | Category | Cases | |
|---|---|---|---|
| 2008 | 1 |
0.6%
|
|
| 2009 | 1 |
0.6%
|
|
| 2010 | 7 |
4.5%
|
|
| 2011 | 15 |
9.7%
|
|
| 2012 | 31 |
20.1%
|
|
| 2013 | 47 |
30.5%
|
|
| 2014 | 21 |
13.6%
|
|
| 2015 | 8 |
5.2%
|
|
| 2016 | 16 |
10.4%
|
|
| 2017 | 7 |
4.5%
|