| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 3716 |
59.3%
|
| 2 | SOME DIFFICULTY | 74 |
1.2%
|
| 3 | A LOT OF DIFFICULTY | 14 |
0.2%
|
| 4 | CANNOT SEE AT ALL | 1 |
0%
|
| 9 | NO RESPONSE | 2 |
0%
|
| Sysmiss | 2462 |
39.3%
|