| Value | Category | Cases | |
|---|---|---|---|
| 0 | Neither certificate or registered | 2 |
40%
|
| 1 | Has certificate | 2 |
40%
|
| 2 | Registered | 1 |
20%
|
| 8 | DK | 0 |
0%
|
| Sysmiss | 9052 |