| Valeur | Catégorie | le cas | |
|---|---|---|---|
| 0 | Neither certificate or registered | 19 |
4.1%
|
| 1 | Has certificate | 390 |
84.2%
|
| 2 | Registered | 50 |
10.8%
|
| 8 | Don't know | 4 |
0.9%
|
| 9 | 36 | ||
| Sysmiss | 3983 |