| Value | Category | Cases | |
|---|---|---|---|
| 1 | 1. No difficulty | 1504 |
97.6%
|
| 2 | 2. Some difficulty | 22 |
1.4%
|
| 3 | 3. A lot of difficulty | 12 |
0.8%
|
| 4 | 4. Cannot do at all | 3 |
0.2%
|
| Sysmiss | 177 |