| Value | Category | Cases | |
|---|---|---|---|
| 2008 | 508 |
3.7%
|
|
| 2009 | 488 |
3.6%
|
|
| 2010 | 9 |
0.1%
|
|
| 9999 | Missing | 2 |
0%
|
| Sysmiss | 12580 |
92.6%
|