| Value | Category | Cases | |
|---|---|---|---|
| 1 | No, never | 173966 |
97.6%
|
| 2 | Yes, once | 3981 |
2.2%
|
| 3 | Yes, twice or more | 338 |
0.2%
|
| 7 | N/A | 55702 | |
| 8 | Invalid | 405 | |
| 9 | Missing | 36931 |