| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 16596 |
82.7%
|
| 2 | SOME DIFFICULTY | 2894 |
14.4%
|
| 3 | A LOT OF DIFFICULTY | 451 |
2.2%
|
| 4 | CANNOT CONCENTRATE AT ALL | 124 |
0.6%
|
| 9 | NO RESPONSE | 12 |
0.1%
|
| Sysmiss | 145 |