| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 2906 |
84.9%
|
| 2 | SOME DIFFICULTY | 326 |
9.5%
|
| 3 | A LOT OF DIFFICULTY | 13 |
0.4%
|
| 4 | CANNOT SEE AT ALL | 1 |
0%
|
| 9 | NO RESPONSE | 2 |
0.1%
|
| Sysmiss | 175 |
5.1%
|