| Value | Category | Cases | |
|---|---|---|---|
| 2007 | 13 |
6.4%
|
|
| 2008 | 33 |
16.3%
|
|
| 2009 | 43 |
21.2%
|
|
| 2010 | 63 |
31%
|
|
| 2011 | 50 |
24.6%
|
|
| 2012 | 1 |
0.5%
|
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 425 |