| Value | Category | Cases | |
|---|---|---|---|
| 2003 | 2 |
0.7%
|
|
| 2004 | 4 |
1.5%
|
|
| 2005 | 2 |
0.7%
|
|
| 2006 | 3 |
1.1%
|
|
| 2007 | 6 |
2.2%
|
|
| 2008 | 5 |
1.8%
|
|
| 2009 | 12 |
4.4%
|
|
| 2010 | 13 |
4.8%
|
|
| 2011 | 9 |
3.3%
|
|
| 2012 | 16 |
5.9%
|
|
| 2013 | 15 |
5.5%
|
|
| 2014 | 24 |
8.8%
|
|
| 2015 | 26 |
9.6%
|
|
| 2016 | 28 |
10.3%
|
|
| 2017 | 36 |
13.2%
|
|
| 2018 | 28 |
10.3%
|
|
| 2019 | 31 |
11.4%
|
|
| Dont Know | 12 |
4.4%
|