| Value | Category |
|---|---|
| 1 | Never any schooling |
| 2 | Some nursery school |
| 3 | 1st grade |
| 4 | 2nd " |
| 5 | 3rd " |
| 6 | 4th " |
| 7 | 5th " |
| 8 | 6th " complete |
| 9 | 7th " |
| 10 | 8th " |
| 11 | 9th " |
| 12 | 10th " |
| 13 | 11th " |
| 14 | 12th " |
| 15 | Higher educ. incomplete |
| 16 | Higher educ. complete |
| 17 | University incomplete |
| 18 | University complete |
| 19 | Adult literacy certificate |
| 20 | Other literacy certificate |
| 30 | Other |