| Valeur | Catégorie | le cas | |
|---|---|---|---|
| 0 | neither certificate or registered | 5 |
20%
|
| 1 | has certificate | 16 |
64%
|
| 2 | registered | 3 |
12%
|
| 8 | don't know | 1 |
4%
|
| Sysmiss | 13226 |