| Value | Category | Cases | |
|---|---|---|---|
| 1 | Never | 1916 |
87.6%
|
| 2 | Once | 94 |
4.3%
|
| 3 | Twice | 46 |
2.1%
|
| 4 | 3-5 times | 37 |
1.7%
|
| 5 | 6-10 times | 27 |
1.2%
|
| 6 | 11-20 times | 18 |
0.8%
|
| 7 | More than 20 times | 38 |
1.7%
|
| 8 | Not applicable | 11 |
0.5%
|
| Sysmiss | 1 |