| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 1 | 
                                    
                                    0.5%
                                 | 
| -9 | Don't know (spontaneous) | 20 | 
                                    
                                    9%
                                 | 
| 0 | 30 | 
                                    
                                    13.5%
                                 | |
| 2 | 1 | 
                                    
                                    0.5%
                                 | |
| 3 | 5 | 
                                    
                                    2.3%
                                 | |
| 4 | 6 | 
                                    
                                    2.7%
                                 | |
| 5 | 12 | 
                                    
                                    5.4%
                                 | |
| 6 | 3 | 
                                    
                                    1.4%
                                 | |
| 7 | 2 | 
                                    
                                    0.9%
                                 | |
| 8 | 4 | 
                                    
                                    1.8%
                                 | |
| 9 | 3 | 
                                    
                                    1.4%
                                 | |
| 10 | 15 | 
                                    
                                    6.8%
                                 | |
| 11 | 3 | 
                                    
                                    1.4%
                                 | |
| 12 | 2 | 
                                    
                                    0.9%
                                 | |
| 14 | 3 | 
                                    
                                    1.4%
                                 | |
| 15 | 13 | 
                                    
                                    5.9%
                                 | |
| 16 | 1 | 
                                    
                                    0.5%
                                 | |
| 18 | 3 | 
                                    
                                    1.4%
                                 | |
| 20 | 18 | 
                                    
                                    8.1%
                                 | |
| 24 | 2 | 
                                    
                                    0.9%
                                 | |
| 25 | 3 | 
                                    
                                    1.4%
                                 | |
| 27 | 1 | 
                                    
                                    0.5%
                                 | |
| 30 | 19 | 
                                    
                                    8.6%
                                 | |
| 35 | 1 | 
                                    
                                    0.5%
                                 | |
| 38 | 1 | 
                                    
                                    0.5%
                                 | |
| 40 | 11 | 
                                    
                                    5%
                                 | |
| 50 | 2 | 
                                    
                                    0.9%
                                 | |
| 55 | 2 | 
                                    
                                    0.9%
                                 | |
| 60 | 5 | 
                                    
                                    2.3%
                                 | |
| 65 | 2 | 
                                    
                                    0.9%
                                 | |
| 70 | 7 | 
                                    
                                    3.2%
                                 | |
| 75 | 2 | 
                                    
                                    0.9%
                                 | |
| 80 | 3 | 
                                    
                                    1.4%
                                 | |
| 90 | 4 | 
                                    
                                    1.8%
                                 | |
| 100 | 5 | 
                                    
                                    2.3%
                                 | |
| 165 | 1 | 
                                    
                                    0.5%
                                 | |
| 220 | 1 | 
                                    
                                    0.5%
                                 | |
| 350 | 1 | 
                                    
                                    0.5%
                                 | |
| 450 | 1 | 
                                    
                                    0.5%
                                 | |
| 500 | 1 | 
                                    
                                    0.5%
                                 | |
| 800 | 2 | 
                                    
                                    0.9%
                                 | |
| Sysmiss | 138 |