| Value | Category | Cases | |
|---|---|---|---|
| 1 | 1. higher grade | 5 |
10%
|
| 2 | 2. standard grade | 10 |
20%
|
| 3 | 3. lower grade | 0 |
0%
|
| 7 | 7. did not take | 33 |
66%
|
| 9 | 9. don't know | 2 |
4%
|
| Sysmiss | 949 |