| Value | Category | Cases | |
|---|---|---|---|
| 1 | a.No difficulty | 10386 |
44.9%
|
| 2 | b.Some difficulty | 109 |
0.5%
|
| 3 | c.A lot of difficulty | 32 |
0.1%
|
| 4 | d.Cannot do at all | 4 |
0%
|
| Missing value | 12607 |
54.5%
|