| Value | Category | Cases | |
|---|---|---|---|
| 1 | a.No difficulty | 2506 |
10.5%
|
| 2 | b.Some difficulty | 46 |
0.2%
|
| 3 | c.A lot of difficulty | 26 |
0.1%
|
| 4 | d.Cannot do at all | 11 |
0%
|
| Missing value | 21365 |
89.2%
|