| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 2117 |
60.9%
|
| 2 | SOME DIFFICULTY | 48 |
1.4%
|
| 3 | A LOT OF DIFFICULTY | 8 |
0.2%
|
| 4 | CANNOT SEE AT ALL | 1 |
0%
|
| 9 | NO RESPONSE | 3 |
0.1%
|
| Sysmiss | 1297 |
37.3%
|