| Value | Category | Cases | |
|---|---|---|---|
| 2004 | 1 |
4.5%
|
|
| 2005 | 7 |
31.8%
|
|
| 2006 | 14 |
63.6%
|
|
| 9999 | 9999. Don't know | 0 |
0%
|
| Sysmiss | 977 |