| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 2 | 
                                                                 
                                    
                                    6.1%
                                 
                                                             | 
                                                        
                    
| 0 | Less than one day | 5 | 
                                                                 
                                    
                                    15.2%
                                 
                                                             | 
                                                        
                    
| 3 | 1 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 6 | 1 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 7 | 5 | 
                                                                 
                                    
                                    15.2%
                                 
                                                             | 
                                                        
                    |
| 8 | 1 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 10 | 4 | 
                                                                 
                                    
                                    12.1%
                                 
                                                             | 
                                                        
                    |
| 11 | 2 | 
                                                                 
                                    
                                    6.1%
                                 
                                                             | 
                                                        
                    |
| 15 | 3 | 
                                                                 
                                    
                                    9.1%
                                 
                                                             | 
                                                        
                    |
| 20 | 3 | 
                                                                 
                                    
                                    9.1%
                                 
                                                             | 
                                                        
                    |
| 25 | 2 | 
                                                                 
                                    
                                    6.1%
                                 
                                                             | 
                                                        
                    |
| 30 | 1 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 40 | 1 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 50 | 1 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| 60 | 1 | 
                                                                 
                                    
                                    3%
                                 
                                                             | 
                                                        
                    |
| Sysmiss | 342 |