| Value | Category | Cases | |
|---|---|---|---|
| 1 | Within past month | 1035 |
32.1%
|
| 2 | Within past 3 months | 745 |
23.1%
|
| 3 | Within 6 months | 456 |
14.2%
|
| 4 | More than 6 months ago | 986 |
30.6%
|
| Sysmiss | 9258 |