| Value | Category | Cases | |
|---|---|---|---|
| 1 | NO DIFFICULTY | 2692 |
96.3%
|
| 2 | SOME DIFFICULTY | 36 |
1.3%
|
| 3 | A LOT OF DIFFICULTY | 7 |
0.3%
|
| 4 | CANNOT SEE AT ALL | 4 |
0.1%
|
| Sysmiss | 55 |
2%
|