| Value | Category | 
|---|---|
| -9 | Don't know | 
| -7 | Legal skip | 
| -6 | Unfinished questionnaire | 
| -3 | Interviewer error | 
| 1 | No grade completed | 
| 2 | soviet system:primary (grades 1-3) | 
| 3 | soviet system:basic general education (grades 4-8) | 
| 4 | soviet system:secondary (grades 9-10) | 
| 5 | soviet system:preliminary vocational education (vocational technical schools) | 
| 6 | soviet system:middle vocational education (public specialized secondary schools) | 
| 7 | soviet system:higher education establishments | 
| 8 | present system:primary (grades 1-4) | 
| 9 | present system:basic general education (grades 5-9) | 
| 10 | present system:secondary general education (grades 10-12) | 
| 11 | present system:preliminary vocational education (professional secondary education (after basic) | 
| 12 | present system:middle vocational education (secondary specialized education (after basic) | 
| 13 | present system:bachelor degree | 
| 14 | present system:masters degree | 
| 15 | Secondary specialized education (after Secondary) | 
| 16 | Candidate of Sience | 
| 17 | Doctor of Science | 
| Sysmiss |