| Value | Category | Cases | |
|---|---|---|---|
| 1 | yes | 434 | 
                                    
                                    18.6%
                                 | 
| 2 | no | 1873 | 
                                    
                                    80.5%
                                 | 
| 3 | (dk) | 19 | 
                                    
                                    0.8%
                                 | 
| 4 | (ref) | 2 | 
                                    
                                    0.1%
                                 | 
| Sysmiss | 672 |