| Value | Category |
|---|---|
| 1 | Primary 2 |
| 2 | First Level |
| 3 | Primary 3 |
| 4 | Primary 5 |
| 5 | None |
| 6 | Low Sec 3 |
| 7 | Low Sec 2 |
| 8 | Primary 4 |
| 9 | High level/University |
| 10 | Primary 6 |
| 11 | Middle Level |
| 12 | Upp sec 3 |
| 13 | Primary 1 |
| 14 | Post Graduate level |
| 15 | Low Sec 1 |
| 16 | Upp sec 2 |
| 17 | Low Sec 4 |
| 18 | Other |
| 19 | Upp sec 1 |
| 20 | 99 |
| Sysmiss |