| Value | Category | Cases | |
|---|---|---|---|
| -99 | Don't know | 0 | 
                                    
                                    0%
                                 | 
| 0 | Less than 1 Year | 0 | 
                                    
                                    0%
                                 | 
| 2 | 3 | 
                                    
                                    25%
                                 | |
| 3 | 3 | 
                                    
                                    25%
                                 | |
| 5 | 1 | 
                                    
                                    8.3%
                                 | |
| 10 | 1 | 
                                    
                                    8.3%
                                 | |
| 15 | 2 | 
                                    
                                    16.7%
                                 | |
| 18 | 1 | 
                                    
                                    8.3%
                                 | |
| 20 | 1 | 
                                    
                                    8.3%
                                 | |
| Sysmiss | 116 |