| 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 |