| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 5090 |
95%
|
| 2 | SOME DIFFICULTY | 229 |
4.3%
|
| 3 | A LOT OF DIFFICULTY | 29 |
0.5%
|
| 4 | CANNOT SEE AT ALL | 10 |
0.2%
|
| 9 | NO RESPONSE | 1 |
0%
|
| Sysmiss | 1 |