| Value | Category |
|---|---|
| -999 | Don't know |
| -888 | Refuse to answer |
| -666 | Other (please specify) |
| None | |
| 1 | Pre-school |
| 11 | P1 |
| 12 | P2 |
| 13 | P3 |
| 14 | P4 |
| 15 | P5 |
| 16 | P6 |
| 17 | JSS1 |
| 18 | JSS2 |
| 19 | JSS3 |
| 20 | M1 |
| 21 | M2 |
| 22 | M3 |
| 23 | M4 |
| 24 | SSS1 |
| 25 | SSS2 |
| 26 | SSS3 |
| 27 | SSS4 |
| 28 | S1 |
| 29 | S2 |
| 30 | S3 |
| 31 | S4 |
| 32 | S5 |
| 33 | L6 |
| 34 | U6 |
| 101 | .R |
| Sysmiss |