| Value | Category | Cases | |
|---|---|---|---|
| 0 | neither certificate or registered | 46 |
1.8%
|
| 1 | has certificate | 0 |
0%
|
| 2 | registered | 2404 |
95.5%
|
| 6 | other | 24 |
1%
|
| 8 | don't know | 44 |
1.7%
|
| Sysmiss | 42096 |