| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 17 | 
                                                                 
                                    
                                    4.5%
                                 
                                                             | 
                                                        
                    
| 1 | Never | 89 | 
                                                                 
                                    
                                    23.7%
                                 
                                                             | 
                                                        
                    
| 2 | Once a week | 177 | 
                                                                 
                                    
                                    47.2%
                                 
                                                             | 
                                                        
                    
| 3 | Between 2 and 4 times a week | 58 | 
                                                                 
                                    
                                    15.5%
                                 
                                                             | 
                                                        
                    
| 4 | Daily | 28 | 
                                                                 
                                    
                                    7.5%
                                 
                                                             | 
                                                        
                    
| 5 | More than once a day | 6 | 
                                                                 
                                    
                                    1.6%
                                 
                                                             | 
                                                        
                    
| Sysmiss | 1071 |