| Value | Category | Cases | |
|---|---|---|---|
| 1 | Within past month | 7 |
18.4%
|
| 2 | Within past 3 months | 11 |
28.9%
|
| 3 | Within 6 months | 3 |
7.9%
|
| 4 | More than 6 months ago | 17 |
44.7%
|
| Sysmiss | 12442 |