| Value | Category | Cases | |
|---|---|---|---|
| 1995 | 1 |
6.7%
|
|
| 2006 | 3 |
20%
|
|
| 2008 | 1 |
6.7%
|
|
| 2009 | 4 |
26.7%
|
|
| 2010 | 2 |
13.3%
|
|
| 2011 | 4 |
26.7%
|
|
| Sysmiss | 446 |