| Value | Category | Cases | |
|---|---|---|---|
| 1 | No-no difficulty | 19884 |
97.9%
|
| 2 | Yes-some difficulty | 154 |
0.8%
|
| 3 | Yes- a lot of difficulty | 171 |
0.8%
|
| 4 | can not do at all | 104 |
0.5%
|
| Sysmiss | 56357 |