| Value | Category | Cases | |
|---|---|---|---|
| 1 | yes | 1970 | 
                                    
                                    96.1%
                                 | 
| 2 | no | 76 | 
                                    
                                    3.7%
                                 | 
| 8 | dk | 3 | 
                                    
                                    0.1%
                                 | 
| Sysmiss | 13302 |