| Value | Category | Cases | |
|---|---|---|---|
| 2008 | 487 |
46%
|
|
| 2009 | 556 |
52.5%
|
|
| 2010 | 11 |
1%
|
|
| 9999 | Missing | 5 |
0.5%
|
| Sysmiss | 12528 |