| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 6 | 
                                    
                                    1.5%
                                 | 
| 1 | Yes | 26 | 
                                    
                                    6.5%
                                 | 
| 2 | No | 369 | 
                                    
                                    92%
                                 | 
| Sysmiss | 554 |