| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 | 
                                    
                                    7.3%
                                 | 
| -6 | Still in progress | 1 | 
                                    
                                    2.4%
                                 | 
| 1 | One week or less | 19 | 
                                    
                                    46.3%
                                 | 
| 2 | 10 | 
                                    
                                    24.4%
                                 | |
| 3 | 1 | 
                                    
                                    2.4%
                                 | |
| 4 | 1 | 
                                    
                                    2.4%
                                 | |
| 6 | 1 | 
                                    
                                    2.4%
                                 | |
| 8 | 1 | 
                                    
                                    2.4%
                                 | |
| 14 | 2 | 
                                    
                                    4.9%
                                 | |
| 16 | 1 | 
                                    
                                    2.4%
                                 | |
| 24 | 1 | 
                                    
                                    2.4%
                                 | |
| Sysmiss | 70 |