| Value | Category | Cases | |
|---|---|---|---|
| 2009 | 7 |
30.4%
|
|
| 2010 | 3 |
13%
|
|
| 2011 | 4 |
17.4%
|
|
| 2012 | 5 |
21.7%
|
|
| 2013 | 4 |
17.4%
|
|
| Sysmiss | 27 |