| Value | Category | Cases | |
|---|---|---|---|
| 0 | None | 40 |
4.6%
|
| 1 | Primary | 105 |
12%
|
| 2 | Lower secondary | 309 |
35.4%
|
| 3 | Upper secondary or higher | 191 |
21.9%
|
| Sysmiss | 229 |
26.2%
|