| Value | Category | Cases | |
|---|---|---|---|
| 1 | No-no difficulty | 19933 |
98.2%
|
| 2 | Yes-some difficulty | 181 |
0.9%
|
| 3 | Yes- a lot of difficulty | 120 |
0.6%
|
| 4 | can not do at all | 72 |
0.4%
|
| Sysmiss | 56364 |