| Value | Category | Cases | |
|---|---|---|---|
| 2011 | 9 |
6%
|
|
| 2012 | 87 |
58.4%
|
|
| 2013 | 10 |
6.7%
|
|
| 9999 | 43 |
28.9%
|
|
| Sysmiss | 31 |