| Value | Category | Cases | |
|---|---|---|---|
| 0 | 0. No difficulty | 3604 |
51.1%
|
| 1 | 1. Minor difficulty | 3052 |
43.2%
|
| 2 | 2. Big difficulty | 166 |
2.4%
|
| 3 | 3. Not applicable | 235 |
3.3%
|