| Value | Category | Cases | |
|---|---|---|---|
| 1 | No, never | 296759 |
97.1%
|
| 2 | Yes, once | 8116 |
2.7%
|
| 3 | Yes, twice or more | 812 |
0.3%
|
| 7 | N/A | 104236 | |
| 8 | Invalid | 571 | |
| 9 | Missing | 74996 |