| Value | Category | 
|---|---|
| -9 | Don't know | 
| -7 | Legal skip | 
| -6 | Unfinished questionnaire | 
| -3 | Interviewer error | 
| 1 | No formal education or less than Primary | 
| 2 | Primary education (3-4 years) | 
| 3 | Basic general education | 
| 4 | Secondary (general attestat/ professional/ secondary vocational) | 
| 5 | Post secondary Specialized vocational / other non-tertiary | 
| 6 | Bachelor degree | 
| 7 | Masters degree (or Higher Education diploma) | 
| 8 | Candidate of Science | 
| 9 | Doctor of Science |