| Value | Category | Cases | |
|---|---|---|---|
| 0 | 0. No difficulty | 4762 |
67.5%
|
| 1 | 1. Minor difficulty | 2153 |
30.5%
|
| 2 | 2. Big difficulty | 59 |
0.8%
|
| 3 | 3. Not applicable | 83 |
1.2%
|