| Value | Category | Cases | |
|---|---|---|---|
| 1 | No-no difficulty | 61487 |
99.5%
|
| 2 | Yes-some difficulty | 124 |
0.2%
|
| 3 | Yes- a lot of difficulty | 118 |
0.2%
|
| 4 | can not do at all | 77 |
0.1%
|
| Sysmiss | 8618 |