| Value | Category |
|---|---|
| -1 | missing |
| 0 | no formal schooling |
| 1 | informal schooling only |
| 2 | some primary schooling |
| 3 | primary school completed |
| 4 | some secondary school/high school |
| 5 | secondary school completed/high school |
| 6 | post-secondary qualifications, not university |
| 7 | some university |
| 8 | university completed |
| 9 | post-graduate |
| 99 | don't know |
| 998 | refused |