| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 1994 |
57.4%
|
| 2 | SOME DIFFICULTY | 157 |
4.5%
|
| 3 | A LOT OF DIFFICULTY | 13 |
0.4%
|
| 4 | CANNOT SEE AT ALL | 9 |
0.3%
|
| 9 | NO RESPONSE | 4 |
0.1%
|
| Sysmiss | 1297 |
37.3%
|