| Value | Category | Cases | |
|---|---|---|---|
| 0 | No | 4552 |
92.7%
|
| 1 | Yes, once | 226 |
4.6%
|
| 2 | Yes, more than once | 132 |
2.7%
|
| 9 | 52 | ||
| Sysmiss | 7857 |