| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 3 | 
                                    
                                    2.7%
                                 | 
| 1 | One year or less | 6 | 
                                    
                                    5.4%
                                 | 
| 2 | 1 | 
                                    
                                    0.9%
                                 | |
| 3 | 3 | 
                                    
                                    2.7%
                                 | |
| 4 | 2 | 
                                    
                                    1.8%
                                 | |
| 5 | 1 | 
                                    
                                    0.9%
                                 | |
| 6 | 5 | 
                                    
                                    4.5%
                                 | |
| 7 | 1 | 
                                    
                                    0.9%
                                 | |
| 8 | 2 | 
                                    
                                    1.8%
                                 | |
| 10 | 10 | 
                                    
                                    9%
                                 | |
| 11 | 1 | 
                                    
                                    0.9%
                                 | |
| 12 | 3 | 
                                    
                                    2.7%
                                 | |
| 13 | 2 | 
                                    
                                    1.8%
                                 | |
| 14 | 1 | 
                                    
                                    0.9%
                                 | |
| 15 | 9 | 
                                    
                                    8.1%
                                 | |
| 16 | 2 | 
                                    
                                    1.8%
                                 | |
| 17 | 1 | 
                                    
                                    0.9%
                                 | |
| 18 | 5 | 
                                    
                                    4.5%
                                 | |
| 19 | 1 | 
                                    
                                    0.9%
                                 | |
| 20 | 7 | 
                                    
                                    6.3%
                                 | |
| 22 | 1 | 
                                    
                                    0.9%
                                 | |
| 25 | 6 | 
                                    
                                    5.4%
                                 | |
| 26 | 1 | 
                                    
                                    0.9%
                                 | |
| 30 | 11 | 
                                    
                                    9.9%
                                 | |
| 32 | 1 | 
                                    
                                    0.9%
                                 | |
| 34 | 2 | 
                                    
                                    1.8%
                                 | |
| 35 | 5 | 
                                    
                                    4.5%
                                 | |
| 36 | 5 | 
                                    
                                    4.5%
                                 | |
| 37 | 1 | 
                                    
                                    0.9%
                                 | |
| 39 | 1 | 
                                    
                                    0.9%
                                 | |
| 40 | 1 | 
                                    
                                    0.9%
                                 | |
| 42 | 1 | 
                                    
                                    0.9%
                                 | |
| 43 | 2 | 
                                    
                                    1.8%
                                 | |
| 48 | 1 | 
                                    
                                    0.9%
                                 | |
| 50 | 3 | 
                                    
                                    2.7%
                                 | |
| 55 | 1 | 
                                    
                                    0.9%
                                 | |
| 60 | 1 | 
                                    
                                    0.9%
                                 | |
| 65 | 1 | 
                                    
                                    0.9%
                                 |