| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 5 |
1.3%
|
| -7 | Does not apply (spontaneous) | 3 |
0.8%
|
| 1 | Very easy | 143 |
36.3%
|
| 2 | Easy | 185 |
47%
|
| 3 | Difficult | 47 |
11.9%
|
| 4 | Very Difficult | 11 |
2.8%
|
| Sysmiss | 625 |