| Value | Category | Cases | |
|---|---|---|---|
| 0 | no difficulty | 8111 |
99%
|
| 1 | Some difficulty | 38 |
0.5%
|
| 2 | Great difficulty | 25 |
0.3%
|
| 3 | Can not completely | 9 |
0.1%
|
| Sysmiss | 6 |