| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 1 | 
                                    
                                    0.3%
                                 | 
| 1 | One year or less | 3 | 
                                    
                                    0.8%
                                 | 
| 2 | 2 | 
                                    
                                    0.6%
                                 | |
| 3 | 3 | 
                                    
                                    0.8%
                                 | |
| 4 | 5 | 
                                    
                                    1.4%
                                 | |
| 5 | 4 | 
                                    
                                    1.1%
                                 | |
| 6 | 6 | 
                                    
                                    1.7%
                                 | |
| 7 | 10 | 
                                    
                                    2.8%
                                 | |
| 8 | 12 | 
                                    
                                    3.3%
                                 | |
| 9 | 7 | 
                                    
                                    1.9%
                                 | |
| 10 | 25 | 
                                    
                                    6.9%
                                 | |
| 11 | 7 | 
                                    
                                    1.9%
                                 | |
| 12 | 17 | 
                                    
                                    4.7%
                                 | |
| 13 | 12 | 
                                    
                                    3.3%
                                 | |
| 14 | 16 | 
                                    
                                    4.4%
                                 | |
| 15 | 26 | 
                                    
                                    7.2%
                                 | |
| 16 | 11 | 
                                    
                                    3%
                                 | |
| 17 | 9 | 
                                    
                                    2.5%
                                 | |
| 18 | 9 | 
                                    
                                    2.5%
                                 | |
| 19 | 16 | 
                                    
                                    4.4%
                                 | |
| 20 | 33 | 
                                    
                                    9.1%
                                 | |
| 21 | 13 | 
                                    
                                    3.6%
                                 | |
| 22 | 5 | 
                                    
                                    1.4%
                                 | |
| 23 | 4 | 
                                    
                                    1.1%
                                 | |
| 24 | 13 | 
                                    
                                    3.6%
                                 | |
| 25 | 12 | 
                                    
                                    3.3%
                                 | |
| 26 | 4 | 
                                    
                                    1.1%
                                 | |
| 27 | 3 | 
                                    
                                    0.8%
                                 | |
| 28 | 6 | 
                                    
                                    1.7%
                                 | |
| 29 | 3 | 
                                    
                                    0.8%
                                 | |
| 30 | 18 | 
                                    
                                    5%
                                 | |
| 31 | 3 | 
                                    
                                    0.8%
                                 | |
| 32 | 5 | 
                                    
                                    1.4%
                                 | |
| 33 | 8 | 
                                    
                                    2.2%
                                 | |
| 34 | 5 | 
                                    
                                    1.4%
                                 | |
| 35 | 5 | 
                                    
                                    1.4%
                                 | |
| 36 | 1 | 
                                    
                                    0.3%
                                 | |
| 37 | 2 | 
                                    
                                    0.6%
                                 | |
| 39 | 2 | 
                                    
                                    0.6%
                                 | |
| 40 | 12 | 
                                    
                                    3.3%
                                 | |
| 42 | 2 | 
                                    
                                    0.6%
                                 | |
| 43 | 1 | 
                                    
                                    0.3%
                                 | |
| 44 | 1 | 
                                    
                                    0.3%
                                 | |
| 45 | 1 | 
                                    
                                    0.3%
                                 |