| Value | Category | Cases | |
|---|---|---|---|
| 1 | Once | 1939 |
38.9%
|
| 2 | Twice | 1181 |
23.7%
|
| 3 | Three times | 531 |
10.7%
|
| 4 | More than three times | 409 |
8.2%
|
| 5 | 1 |
0%
|
|
| 6 | 1 |
0%
|
|
| 7 | N/a | 920 |
18.5%
|
| Sysmiss | 18256 |