| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 23 | 
                                    
                                    3.1%
                                 | 
| 1 | Yes | 269 | 
                                    
                                    36.3%
                                 | 
| 2 | No | 449 | 
                                    
                                    60.6%
                                 | 
| Sysmiss | 675 |