| Value | Category | Cases | |
|---|---|---|---|
| 2007 | 12 |
6.9%
|
|
| 2008 | 23 |
13.3%
|
|
| 2009 | 36 |
20.8%
|
|
| 2010 | 56 |
32.4%
|
|
| 2011 | 45 |
26%
|
|
| 2012 | 1 |
0.6%
|
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 455 |