| Value | Category | Cases | |
|---|---|---|---|
| 1968 | 2 |
1.2%
|
|
| 2000 | 2 |
1.2%
|
|
| 2003 | 2 |
1.2%
|
|
| 2004 | 1 |
0.6%
|
|
| 2005 | 4 |
2.3%
|
|
| 2006 | 2 |
1.2%
|
|
| 2007 | 3 |
1.7%
|
|
| 2009 | 7 |
4%
|
|
| 2010 | 2 |
1.2%
|
|
| 2011 | 7 |
4%
|
|
| 2012 | 10 |
5.8%
|
|
| 2013 | 14 |
8.1%
|
|
| 2014 | 23 |
13.3%
|
|
| 2015 | 38 |
22%
|
|
| 2016 | 25 |
14.5%
|
|
| 2017 | 24 |
13.9%
|
|
| 2018 | 7 |
4%
|