| Value | Category | Cases | |
|---|---|---|---|
| 1 | No difficulty | 2664895 |
98.7%
|
| 2 | Yes, some difficulty | 24373 |
0.9%
|
| 3 | Yes, a lot of difficulty | 6577 |
0.2%
|
| 4 | Cannot do at all | 2953 |
0.1%
|
| Sysmiss | 384774 |