| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 0 | 
                                    
                                    0%
                                 | 
| 1 | Annually | 16 | 
                                    
                                    48.5%
                                 | 
| 2 | Biannually/Every six months | 0 | 
                                    
                                    0%
                                 | 
| 3 | Quarterly | 0 | 
                                    
                                    0%
                                 | 
| 4 | Monthly | 8 | 
                                    
                                    24.2%
                                 | 
| 5 | Weekly | 1 | 
                                    
                                    3%
                                 | 
| 6 | Daily | 7 | 
                                    
                                    21.2%
                                 | 
| 7 | Hourly | 0 | 
                                    
                                    0%
                                 | 
| 8 | More than once in an hour | 1 | 
                                    
                                    3%
                                 | 
| Sysmiss | 922 |