| Value | Category |
|---|---|
| 0 | None |
| 1 | Primary |
| 2 | Lower Secondary |
| 3 | Upper Secondary |
| 4 | Certificate (<1 yr) |
| 5 | Training Diploma (1-2 years) |
| 6 | Tech./Prof.Secondary School |
| 7 | Junior College |
| 8 | Associates Degree |
| 9 | Bachelors |
| 10 | Masters |
| 11 | Sub-Doctor |
| 12 | PHD |
| 13 | Don't know |
| Sysmiss |