| Value | Category | Cases | |
|---|---|---|---|
| 2007 | 7 |
7.4%
|
|
| 2008 | 25 |
26.6%
|
|
| 2009 | 18 |
19.1%
|
|
| 2010 | 24 |
25.5%
|
|
| 2011 | 19 |
20.2%
|
|
| 2012 | 1 |
1.1%
|
|
| 9999 | Missing | 0 |
0%
|
| Sysmiss | 666 |