| Value | Category | Cases | |
|---|---|---|---|
| 1 | All | 447 |
25.7%
|
| 2 | More than half | 12 |
0.7%
|
| 3 | Half | 5 |
0.3%
|
| 4 | less than half | 23 |
1.3%
|
| 5 | None | 345 |
19.9%
|
| 9 | No textbook | 906 |
52.1%
|