| Value | Category | Cases | |
|---|---|---|---|
| 0 | never | 917 | 
                                                                 
                                    
                                    32.7%
                                 
                                                             | 
                                                        
                    
| 1 | once or twice | 1018 | 
                                                                 
                                    
                                    36.3%
                                 
                                                             | 
                                                        
                    
| 2 | more often | 867 | 
                                                                 
                                    
                                    30.9%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 3953 |