| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 64 |
41%
|
| 2004 | 1 |
0.6%
|
|
| 2006 | 1 |
0.6%
|
|
| 2007 | 1 |
0.6%
|
|
| 2008 | 4 |
2.6%
|
|
| 9888 | Continuing | 85 |
54.5%
|
| Sysmiss | 30 |