| Value | Category | Cases | |
|---|---|---|---|
| 1 | a. One month | 3452 | 
                                    
                                    95.1%
                                 | 
| 2 | b. 3 months | 6 | 
                                    
                                    0.2%
                                 | 
| 3 | c. 6 months | 3 | 
                                    
                                    0.1%
                                 | 
| 4 | d. 12 months | 162 | 
                                    
                                    4.5%
                                 | 
| 5 | e. Others | 5 | 
                                    
                                    0.1%
                                 | 
| Sysmiss | 878 |