| Value | Category | 
|---|---|
| 0 | Pre-school | 
| 1 | Std 1 | 
| 2 | Std 2 | 
| 3 | Std 3 | 
| 4 | Std 4 | 
| 5 | Std 5 | 
| 6 | Std 6 | 
| 7 | Std 7 | 
| 8 | Std 7 and CPE | 
| 9 | Std 8 | 
| 10 | Std 8 and KCPE | 
| 11 | Form 1 | 
| 12 | Form 2 | 
| 13 | Form 2 and KJSE | 
| 14 | Form 3 | 
| 15 | Form 4 | 
| 16 | Form 4 and KCE/KCSE | 
| 17 | Form 5 | 
| 18 | Form 6 | 
| 19 | Form 6 and A level | 
| 20 | University | 
| 21 | Technical | 
| 22 | Informal | 
| 99 | Not stated | 
| Sysmiss |