| Value | Category | Cases | |
|---|---|---|---|
| 1 | No difficulty | 1920 |
87.1%
|
| 2 | Minor difficult | 130 |
5.9%
|
| 3 | Big difficulty | 142 |
6.4%
|
| 8 | NA | 1 |
0%
|
| 9 | I don’t know | 7 |
0.3%
|
| Sysmiss | 4 |