| Value | Category | Cases | |
|---|---|---|---|
| 0 | NONE | 290 | 
                                    
                                    19.6%
                                 | 
| 1 | ONE | 23 | 
                                    
                                    1.6%
                                 | 
| 2 | TWO | 23 | 
                                    
                                    1.6%
                                 | 
| 3 | THREE | 45 | 
                                    
                                    3%
                                 | 
| 4 | FOUR | 27 | 
                                    
                                    1.8%
                                 | 
| 5 | FIVE | 33 | 
                                    
                                    2.2%
                                 | 
| 6 | SIX | 27 | 
                                    
                                    1.8%
                                 | 
| 7 | SEVEN | 22 | 
                                    
                                    1.5%
                                 | 
| 8 | EIGHT | 13 | 
                                    
                                    0.9%
                                 | 
| 9 | NINE | 25 | 
                                    
                                    1.7%
                                 | 
| 10 | TEN OR MORE BOOKS | 285 | 
                                    
                                    19.3%
                                 | 
| Sysmiss | 666 | 
                                    
                                    45%
                                 |