| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 167 | 
                                    
                                    25.9%
                                 | 
| 1 | One hour or less | 6 | 
                                    
                                    0.9%
                                 | 
| 2 | 3 | 
                                    
                                    0.5%
                                 | |
| 3 | 1 | 
                                    
                                    0.2%
                                 | |
| 4 | 1 | 
                                    
                                    0.2%
                                 | |
| 5 | 1 | 
                                    
                                    0.2%
                                 | |
| 6 | 1 | 
                                    
                                    0.2%
                                 | |
| 7 | 3 | 
                                    
                                    0.5%
                                 | |
| 8 | 2 | 
                                    
                                    0.3%
                                 | |
| 10 | 2 | 
                                    
                                    0.3%
                                 | |
| 12 | 1 | 
                                    
                                    0.2%
                                 | |
| 15 | 1 | 
                                    
                                    0.2%
                                 | |
| 16 | 1 | 
                                    
                                    0.2%
                                 | |
| 18 | 1 | 
                                    
                                    0.2%
                                 | |
| 20 | 2 | 
                                    
                                    0.3%
                                 | |
| 24 | 8 | 
                                    
                                    1.2%
                                 | |
| 25 | 1 | 
                                    
                                    0.2%
                                 | |
| 30 | 104 | 
                                    
                                    16.1%
                                 | |
| 31 | 2 | 
                                    
                                    0.3%
                                 | |
| 32 | 8 | 
                                    
                                    1.2%
                                 | |
| 33 | 4 | 
                                    
                                    0.6%
                                 | |
| 34 | 3 | 
                                    
                                    0.5%
                                 | |
| 35 | 15 | 
                                    
                                    2.3%
                                 | |
| 36 | 12 | 
                                    
                                    1.9%
                                 | |
| 38 | 2 | 
                                    
                                    0.3%
                                 | |
| 40 | 58 | 
                                    
                                    9%
                                 | |
| 42 | 2 | 
                                    
                                    0.3%
                                 | |
| 44 | 2 | 
                                    
                                    0.3%
                                 | |
| 45 | 9 | 
                                    
                                    1.4%
                                 | |
| 48 | 31 | 
                                    
                                    4.8%
                                 | |
| 49 | 1 | 
                                    
                                    0.2%
                                 | |
| 50 | 22 | 
                                    
                                    3.4%
                                 | |
| 52 | 2 | 
                                    
                                    0.3%
                                 | |
| 55 | 1 | 
                                    
                                    0.2%
                                 | |
| 56 | 3 | 
                                    
                                    0.5%
                                 | |
| 58 | 1 | 
                                    
                                    0.2%
                                 | |
| 60 | 19 | 
                                    
                                    2.9%
                                 | |
| 64 | 1 | 
                                    
                                    0.2%
                                 | |
| 65 | 1 | 
                                    
                                    0.2%
                                 | |
| 70 | 5 | 
                                    
                                    0.8%
                                 | |
| 72 | 18 | 
                                    
                                    2.8%
                                 | |
| 73 | 1 | 
                                    
                                    0.2%
                                 | |
| 80 | 21 | 
                                    
                                    3.3%
                                 | |
| 82 | 1 | 
                                    
                                    0.2%
                                 | |
| 83 | 1 | 
                                    
                                    0.2%
                                 | |
| 85 | 1 | 
                                    
                                    0.2%
                                 | |
| 90 | 1 | 
                                    
                                    0.2%
                                 | |
| 92 | 1 | 
                                    
                                    0.2%
                                 | |
| 96 | 7 | 
                                    
                                    1.1%
                                 | |
| 100 | 4 | 
                                    
                                    0.6%
                                 | |
| 120 | 19 | 
                                    
                                    2.9%
                                 | |
| 128 | 1 | 
                                    
                                    0.2%
                                 | |
| 130 | 1 | 
                                    
                                    0.2%
                                 | |
| 150 | 3 | 
                                    
                                    0.5%
                                 | |
| 156 | 1 | 
                                    
                                    0.2%
                                 | |
| 160 | 4 | 
                                    
                                    0.6%
                                 | |
| 168 | 3 | 
                                    
                                    0.5%
                                 | |
| 180 | 1 | 
                                    
                                    0.2%
                                 | |
| 188 | 1 | 
                                    
                                    0.2%
                                 | |
| 200 | 6 | 
                                    
                                    0.9%
                                 | |
| 208 | 3 | 
                                    
                                    0.5%
                                 | |
| 240 | 1 | 
                                    
                                    0.2%
                                 | |
| 248 | 1 | 
                                    
                                    0.2%
                                 | |
| 256 | 1 | 
                                    
                                    0.2%
                                 | |
| 276 | 1 | 
                                    
                                    0.2%
                                 | |
| 280 | 3 | 
                                    
                                    0.5%
                                 | |
| 288 | 7 | 
                                    
                                    1.1%
                                 | |
| 300 | 3 | 
                                    
                                    0.5%
                                 | |
| 320 | 1 | 
                                    
                                    0.2%
                                 | |
| 360 | 6 | 
                                    
                                    0.9%
                                 | |
| 400 | 1 | 
                                    
                                    0.2%
                                 | |
| 440 | 1 | 
                                    
                                    0.2%
                                 | |
| 450 | 2 | 
                                    
                                    0.3%
                                 | |
| 480 | 5 | 
                                    
                                    0.8%
                                 | |
| 672 | 1 | 
                                    
                                    0.2%
                                 | |
| 1000 | 1 | 
                                    
                                    0.2%
                                 | |
| 2304 | 1 | 
                                    
                                    0.2%
                                 |