| Value | Category | Cases | |
|---|---|---|---|
| 1 | ONLY ONCE | 1073 | 
                                    
                                    49.8%
                                 | 
| 2 | MORE THAN ONCE | 246 | 
                                    
                                    11.4%
                                 | 
| 9 | NO RESPONSE | 35 | 
                                    
                                    1.6%
                                 | 
| Sysmiss | 799 | 
                                    
                                    37.1%
                                 |