| Value | Category | Cases | |
|---|---|---|---|
| 0 | Neither certificate or registered | 102 |
44%
|
| 1 | Has certificate | 51 |
22%
|
| 2 | Registered | 72 |
31%
|
| 8 | DK | 7 |
3%
|
| 9 | 3 | ||
| Sysmiss | 8822 |