| Value | Category | Cases | |
|---|---|---|---|
| 1 | Never | 3960 |
87.9%
|
| 2 | Once | 171 |
3.8%
|
| 3 | Twice | 100 |
2.2%
|
| 4 | 3-5 times | 78 |
1.7%
|
| 5 | 6-10 times | 52 |
1.2%
|
| 6 | 11-20 times | 34 |
0.8%
|
| 7 | More than 20 times | 63 |
1.4%
|
| 8 | Not applicable | 11 |
0.2%
|
| Sysmiss | 37 |