| Value | Category | Cases | |
|---|---|---|---|
| 1 | 1. No, no difficulty | 105116 |
98.1%
|
| 2 | 2. Yes, some | 1628 |
1.5%
|
| 3 | 3. Yes, a lot | 263 |
0.2%
|
| 4 | 4. Cannot see | 159 |
0.1%
|
| Sysmiss | 502 |