| Value | Category | Cases | |
|---|---|---|---|
| 1 | No difficulty | 3547 |
92.6%
|
| 2 | Some difficulty | 258 |
6.7%
|
| 3 | A lot of difficulty | 18 |
0.5%
|
| 4 | Cannot do at all | 0 |
0%
|
| 99 | Refused | 6 |
0.2%
|
| Sysmiss | 316 |