| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 | 
                                    
                                    0%
                                 | 
| -9 | Don't know (spontaneous) | 2 | 
                                    
                                    5.3%
                                 | 
| 0 | 21 | 
                                    
                                    55.3%
                                 | |
| 10 | 3 | 
                                    
                                    7.9%
                                 | |
| 12 | 2 | 
                                    
                                    5.3%
                                 | |
| 16 | 1 | 
                                    
                                    2.6%
                                 | |
| 17 | 1 | 
                                    
                                    2.6%
                                 | |
| 20 | 1 | 
                                    
                                    2.6%
                                 | |
| 25 | 1 | 
                                    
                                    2.6%
                                 | |
| 27 | 1 | 
                                    
                                    2.6%
                                 | |
| 90 | 1 | 
                                    
                                    2.6%
                                 | |
| 110 | 1 | 
                                    
                                    2.6%
                                 | |
| 200 | 1 | 
                                    
                                    2.6%
                                 | |
| 230 | 1 | 
                                    
                                    2.6%
                                 | |
| 750 | 1 | 
                                    
                                    2.6%
                                 | |
| Sysmiss | 307 |