| Value | Category | Cases | |
|---|---|---|---|
| 1 | None | 3103 |
95.6%
|
| 2 | Once | 102 |
3.1%
|
| 3 | Twice | 25 |
0.8%
|
| 4 | Three times | 8 |
0.2%
|
| 5 | Four times or more | 9 |
0.3%
|
| Sysmiss | 352 |