| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 25 | 
                                    
                                    21.2%
                                 | 
| 0 | 1 | 
                                    
                                    0.8%
                                 | |
| 1 | 22 | 
                                    
                                    18.6%
                                 | |
| 2 | 13 | 
                                    
                                    11%
                                 | |
| 3 | 15 | 
                                    
                                    12.7%
                                 | |
| 4 | 4 | 
                                    
                                    3.4%
                                 | |
| 5 | 6 | 
                                    
                                    5.1%
                                 | |
| 6 | 1 | 
                                    
                                    0.8%
                                 | |
| 7 | 2 | 
                                    
                                    1.7%
                                 | |
| 10 | 12 | 
                                    
                                    10.2%
                                 | |
| 12 | 3 | 
                                    
                                    2.5%
                                 | |
| 15 | 1 | 
                                    
                                    0.8%
                                 | |
| 17 | 1 | 
                                    
                                    0.8%
                                 | |
| 20 | 7 | 
                                    
                                    5.9%
                                 | |
| 30 | 3 | 
                                    
                                    2.5%
                                 | |
| 35 | 1 | 
                                    
                                    0.8%
                                 | |
| 40 | 1 | 
                                    
                                    0.8%
                                 | |
| Sysmiss | 193 |