| Value | Category | Cases | |
|---|---|---|---|
| 1 | All | 471 |
27.1%
|
| 2 | More than half | 16 |
0.9%
|
| 3 | Half | 10 |
0.6%
|
| 4 | less than half | 17 |
1%
|
| 5 | None | 318 |
18.3%
|
| 9 | No textbook | 906 |
52.1%
|