| Value | Category | Cases | |
|---|---|---|---|
| 0 | easy | 1521 |
30.8%
|
| 1 | moderate | 1125 |
22.8%
|
| 2 | difficult | 2225 |
45.1%
|
| 3 | not applicable | 63 |
1.3%
|
| Sysmiss | 24 |