| Value | Category | Cases | |
|---|---|---|---|
| 0 | never happened | 5494 |
71.9%
|
| 1 | rarely(1-2 times) | 1207 |
15.8%
|
| 2 | sometimes(3-10 times) | 553 |
7.2%
|
| 3 | often(more than 10 times) | 384 |
5%
|
| Sysmiss | 56 |