| Value | Category | 
|---|---|
| -9 | Don't know | 
| -8 | Refused to answer | 
| -7 | Not applicable | 
| -6 | Still in process | 
| -5 | Application denied | 
| -4 | Skipped | 
| -3 | Not provided | 
| 1 | 0-3 years of education | 
| 2 | 4-6 years of education | 
| 3 | 7-12 years of education | 
| 5 | 13 years and above of education | 
| Sysmiss |