| Value | Category | Cases | |
|---|---|---|---|
| 1 | No-no difficulty | 17534 |
86.8%
|
| 2 | Yes-some difficulty | 1922 |
9.5%
|
| 3 | Yes- a lot of difficulty | 721 |
3.6%
|
| 4 | can not do at all | 25 |
0.1%
|
| Sysmiss | 56468 |