| Value | Category | Cases | |
|---|---|---|---|
| 0 | 0. No difficulty | 1825 |
25.9%
|
| 1 | 1. Minor difficulty | 4557 |
64.6%
|
| 2 | 2. Big difficulty | 403 |
5.7%
|
| 3 | 3. Not applicable | 272 |
3.9%
|