| Value | Category | Cases | |
|---|---|---|---|
| 1 | no difficulty seeing | 9938 |
84.8%
|
| 2 | some difficulty | 1421 |
12.1%
|
| 3 | a lot of difficulty | 357 |
3%
|
| 4 | cannot see at all | 3 |
0%
|
| 8 | don't know | 1 |
0%
|
| Sysmiss | 1229 |