| Value | Category | 
|---|---|
| 1 | No formal schooling | 
| 2 | less than primary school | 
| 3 | primary school completed | 
| 4 | secondary school completed | 
| 5 | high school (or equivalent) completed | 
| 6 | college / pre-university / university completed | 
| 7 | post graduate deegree completed | 
| Sysmiss |