| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 7 | 
                                                                 
                                    
                                    2.6%
                                 
                                                             | 
                                                        
                    
| 1 | Never | 20 | 
                                                                 
                                    
                                    7.5%
                                 
                                                             | 
                                                        
                    
| 2 | Once a week | 112 | 
                                                                 
                                    
                                    42.3%
                                 
                                                             | 
                                                        
                    
| 3 | Between 2 and 4 times a week | 55 | 
                                                                 
                                    
                                    20.8%
                                 
                                                             | 
                                                        
                    
| 4 | Daily | 59 | 
                                                                 
                                    
                                    22.3%
                                 
                                                             | 
                                                        
                    
| 5 | More than once a day | 12 | 
                                                                 
                                    
                                    4.5%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 507 |