| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 8426 |
94%
|
| 2 | SOME DIFFICULTY | 471 |
5.3%
|
| 3 | A LOT OF DIFFICULTY | 47 |
0.5%
|
| 4 | CANNOT SEE AT ALL | 2 |
0%
|
| Sysmiss | 19 |
0.2%
|