| Value | Category | Cases | |
|---|---|---|---|
| -9 | Don't know (spontaneous) | 23 | 
                                    
                                    7.4%
                                 | 
| 0 | No time was spent | 79 | 
                                    
                                    25.4%
                                 | 
| 1 | 8 | 
                                    
                                    2.6%
                                 | |
| 2 | 17 | 
                                    
                                    5.5%
                                 | |
| 3 | 9 | 
                                    
                                    2.9%
                                 | |
| 4 | 4 | 
                                    
                                    1.3%
                                 | |
| 5 | 17 | 
                                    
                                    5.5%
                                 | |
| 6 | 4 | 
                                    
                                    1.3%
                                 | |
| 8 | 4 | 
                                    
                                    1.3%
                                 | |
| 10 | 30 | 
                                    
                                    9.6%
                                 | |
| 12 | 1 | 
                                    
                                    0.3%
                                 | |
| 13 | 1 | 
                                    
                                    0.3%
                                 | |
| 15 | 13 | 
                                    
                                    4.2%
                                 | |
| 16 | 3 | 
                                    
                                    1%
                                 | |
| 18 | 2 | 
                                    
                                    0.6%
                                 | |
| 20 | 30 | 
                                    
                                    9.6%
                                 | |
| 21 | 1 | 
                                    
                                    0.3%
                                 | |
| 24 | 2 | 
                                    
                                    0.6%
                                 | |
| 25 | 8 | 
                                    
                                    2.6%
                                 | |
| 30 | 27 | 
                                    
                                    8.7%
                                 | |
| 35 | 4 | 
                                    
                                    1.3%
                                 | |
| 40 | 7 | 
                                    
                                    2.3%
                                 | |
| 45 | 1 | 
                                    
                                    0.3%
                                 | |
| 50 | 11 | 
                                    
                                    3.5%
                                 | |
| 52 | 1 | 
                                    
                                    0.3%
                                 | |
| 80 | 1 | 
                                    
                                    0.3%
                                 | |
| 100 | 3 | 
                                    
                                    1%
                                 |