| Value | Category | Cases | |
|---|---|---|---|
| 1 | 1. No difficulty | 3765364 |
86.8%
|
| 2 | 2. Some difficulty | 144098 |
3.3%
|
| 3 | 3. A lot of difficulty | 42814 |
1%
|
| 4 | 4. Cannot do at all | 29345 |
0.7%
|
| 5 | 5. Do not know | 13511 |
0.3%
|
| 6 | 6. Cannot yet be determined | 190128 |
4.4%
|
| 9 | 9. Unspecified | 152437 |
3.5%
|
| Sysmiss | 80897 |