| Value | Category | Cases | |
|---|---|---|---|
| 1 | Very easy | 187 |
9.2%
|
| 2 | Relatively easy | 472 |
23.3%
|
| 3 | Relatively hard | 835 |
41.3%
|
| 4 | Very hard | 489 |
24.2%
|
| 99 | I'm not sure | 41 |
2%
|
| Sysmiss | 1303 |