| Value | Category | Cases | |
|---|---|---|---|
| 1 | All | 478 |
27.5%
|
| 2 | More than half | 26 |
1.5%
|
| 3 | Half | 13 |
0.7%
|
| 4 | less than half | 14 |
0.8%
|
| 5 | None | 301 |
17.3%
|
| 9 | No textbook | 906 |
52.1%
|