| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 | 
                                    
                                    1.9%
                                 | 
| -4 | Too many to count | 90 | 
                                    
                                    58.1%
                                 | 
| 0 | 1 | 
                                    
                                    0.6%
                                 | |
| 1 | 3 | 
                                    
                                    1.9%
                                 | |
| 2 | 1 | 
                                    
                                    0.6%
                                 | |
| 3 | 7 | 
                                    
                                    4.5%
                                 | |
| 4 | 7 | 
                                    
                                    4.5%
                                 | |
| 5 | 7 | 
                                    
                                    4.5%
                                 | |
| 6 | 2 | 
                                    
                                    1.3%
                                 | |
| 7 | 5 | 
                                    
                                    3.2%
                                 | |
| 8 | 4 | 
                                    
                                    2.6%
                                 | |
| 10 | 4 | 
                                    
                                    2.6%
                                 | |
| 11 | 1 | 
                                    
                                    0.6%
                                 | |
| 12 | 1 | 
                                    
                                    0.6%
                                 | |
| 15 | 7 | 
                                    
                                    4.5%
                                 | |
| 20 | 6 | 
                                    
                                    3.9%
                                 | |
| 38 | 1 | 
                                    
                                    0.6%
                                 | |
| 40 | 1 | 
                                    
                                    0.6%
                                 | |
| 50 | 2 | 
                                    
                                    1.3%
                                 | |
| 150 | 1 | 
                                    
                                    0.6%
                                 | |
| 1000 | 1 | 
                                    
                                    0.6%
                                 | |
| Sysmiss | 2 |