| Value | Category | Cases | |
|---|---|---|---|
| 0 | 1 |
0.1%
|
|
| 1 | Regularly | 24 |
3.1%
|
| 2 | Irregularly | 73 |
9.3%
|
| 3 | When requested | 12 |
1.5%
|
| 4 | Never | 676 |
86%
|
| Sysmiss | 2401 |