| Value | Category | Cases | |
|---|---|---|---|
| 1 | Very difficult | 11159 |
79.7%
|
| 2 | Somewhat difficult | 1885 |
13.5%
|
| 3 | Not difficult at all | 897 |
6.4%
|
| 99 | Do not know | 53 |
0.4%
|